Top 12 vulnerabilities routinely exploited in 2022

CVE-2017-0199 is a remote code execution vulnerability in Microsoft Office and WordPad that stems from improper parsing of specially crafted files. Attackers trigger it by getting a user to open a malicious document, after which attacker-controlled code executes with the privileges of the logged-in user. Anyone running the affected Microsoft Office or WordPad software is exposed, and CISA notes the flaw has been leveraged in ransomware campaigns; no CVSS score is available in the source data. The flaw was added to CISA's Known Exploited Vulnerabilities catalog on 2021-11-03, and EPSS assigns a 99.9% probability of exploitation within 30 days (100th percentile), indicating active, ongoing exploitation.

Do: Apply Microsoft's security updates for Office and Windows per vendor instructions, as required by CISA's KEV catalog; the flaw was publicly reported as fixed in Microsoft's April 2017 security updates. Until patched, treat unsolicited Office documents and email attachments as high-risk, since exploitation requires a user to open a crafted file. Verify that all Office and WordPad installations across the estate—especially endpoints that handle untrusted documents—have received the update.

CVE-2017-11882 is a memory corruption vulnerability (CWE-119) in Microsoft Office, residing in the legacy Microsoft Equation Editor component (EQNEDT32.EXE), that allows remote code execution in the context of the current user. Attackers trigger it by persuading a user to open a crafted document, most commonly an RTF file or other Office document carrying a malicious embedded equation object, which overflows a buffer while the equation content is parsed. Successful exploitation lets the attacker run arbitrary code with the privileges of the signed-in user, a typical foothold for malware delivery and, per CISA, for ransomware operations. Any environment running affected Microsoft Office builds is exposed; the source data does not enumerate specific affected version ranges. The flaw is confirmed exploited in the wild: it was added to the CISA Known Exploited Vulnerabilities catalog on 2021-11-03 with known ransomware use and holds a 99.9% EPSS score (percentile 100), though the source data lists no public PoC.

Do: Apply Microsoft's Office security updates (November 2017 or later) across all endpoints, prioritizing this KEV-listed flaw given its known ransomware use. On systems that cannot yet be patched, disable or unregister the legacy Equation Editor (EQNEDT32.EXE) and consider blocking or warning on RTF attachments as interim mitigations. Check for indicators of abuse such as EQNEDT32.EXE spawning unexpected child processes after document opens.

CVE-2018-13379 is a path traversal flaw (CWE-22) in the Fortinet FortiOS SSL VPN web portal that allows an unauthenticated attacker to download FortiOS system files via specially crafted HTTP resource requests. By traversing directories through crafted requests to the exposed web portal, the attacker can retrieve sensitive files, a technique publicly documented as yielding the SSL VPN session file containing usernames and passwords in plaintext. Any organization running the SSL VPN web portal on a FortiGate appliance is affected, and risk is highest where the portal is directly reachable from the internet. The flaw is confirmed in the wild: it was added to the CISA KEV catalog on 2021-11-03 with known ransomware use, and EPSS assigns it a 100% probability of exploitation within 30 days. No public PoC is listed in the provided data, but credential theft tied to this bug has been widely reused by threat actors.

Do: Apply the patched FortiOS release per Fortinet's vendor advisory immediately, as this is a CISA KEV required action; if the fixed version is not known from this data, follow Fortinet's FG-IR-18-384 advisory for the correct upgrade path. Rotate SSL VPN credentials and review VPN access logs for path-traversal requests, since successful exploitation exposes plaintext session credentials, and restrict SSL VPN portal exposure to trusted sources where possible.

Ivanti Pulse Connect Secure, an enterprise SSL VPN appliance, contains an arbitrary file read vulnerability (CWE-22, path traversal) that requires no authentication. An unauthenticated remote attacker with network access to the appliance over HTTPS can send a specially crafted URI containing traversal sequences to read arbitrary files from the device. The attacker gains access to sensitive appliance files, potentially including configuration or credential material useful for further compromise, and CISA records known ransomware use of this flaw. Any organization running Pulse Connect Secure, especially gateways exposed to the internet for remote access, is affected. Exploitation is established: CISA added the flaw to its Known Exploited Vulnerabilities catalog on 2021-11-03 with known ransomware use, EPSS assigns a 100% probability of exploitation in the next 30 days, and no public PoC is known.

Do: Apply updates per Ivanti's instructions, the required action in the CISA KEV entry, prioritizing internet-facing Pulse Connect Secure gateways, and consult the vendor advisory for the applicable fixed release since no version range is provided here. Where patching is not immediate, restrict HTTPS access to the appliance and hunt for signs of exploitation (unexpected file reads, anomalous VPN logins or sessions, and follow-on ransomware activity), as CISA reports known ransomware use.

CVE-2019-19781 is a path-traversal flaw (classified CWE-22, though CISA's description calls it unspecified) in Citrix ADC (formerly NetScaler ADC), Citrix Gateway, and Citrix SD-WAN WANOP appliances that lets an unauthenticated remote attacker traverse directories via crafted requests and execute arbitrary commands on the appliance, typically with root privileges. It is triggered by sending specially crafted directory-traversal requests (crafted URLs/requests to the appliance's management or VPN endpoints), which lets the attacker write files and run commands with no credentials. Successful exploitation yields arbitrary code execution on the appliance, enabling theft of VPN/ADC credentials, lateral movement into the corporate network, and installation of persistent backdoors. Any organization running affected ADC, Gateway, or SD-WAN WANOP firmware is affected, with internet-facing gateways used for remote access at the highest risk. Exploitation is confirmed in the wild: the vulnerability is on CISA's KEV (added 2021-11-03) with known ransomware use, EPSS assigns near-certain (100.0%) probability of exploitation within 30 days, and no public PoC is listed despite confirmed abuse.

Do: Upgrade Citrix ADC, Gateway, and SD-WAN WANOP appliances to the fixed firmware builds listed in Citrix advisory CTX267020; if patching cannot be done immediately, apply Citrix's published interim mitigation and restrict internet exposure to the appliance. Because exploitation grants root code execution and persistence, after patching hunt for indicators of compromise (unexpected nsroot account, modified system files, crontab/scheduled entries), kill all active and inactive sessions, and rotate appliance and VPN credentials. Prioritize internet-facing gateways and comply with CISA's required action to apply vendor updates.

CVE-2020-1472, widely known as "Zerologon," is an elevation-of-privilege flaw in how the Netlogon secure channel is established over the Netlogon Remote Protocol (MS-NRPC) on Microsoft domain controllers. An unauthenticated attacker with network reachability to a domain controller sends specially crafted Netlogon messages to establish a vulnerable secure channel and then runs a specially crafted application on the network to obtain domain administrator access. Successful exploitation yields domain administrator privileges, effectively full compromise of the Active Directory environment, and the flaw is known to be used in ransomware operations. Any organization running affected Windows Server versions (2008 through 20H2) as domain controllers is exposed, along with environments using Netlogon implementations from Samba and distributions or products from Fedora, openSUSE, Canonical (Ubuntu), Debian, Synology, and Oracle. Exploitation is highly active: a public Zerologon PoC/exploit is available, the flaw is on CISA's Known Exploited Vulnerabilities catalog (added 2021-11-03, with known ransomware use), and EPSS estimates a 99.4% probability of exploitation within 30 days.

Do: Apply the vendor updates on all domain controllers and other affected systems immediately, following Microsoft's two-phase Netlogon secure channel guidance (the enforcement phase of the phased rollout began in Q1 2021). Audit Netlogon secure-channel connections and event logs for clients still using vulnerable connections before enabling full enforcement, and install updated packages for Samba and other Netlogon implementations from Fedora, openSUSE, Ubuntu, Debian, Synology, and Oracle. Given known ransomware use, prioritize patching any domain controller reachable from user networks, VPNs, or the internet.

CVE-2021-20021 is an improper privilege management flaw (CWE-269) in SonicWall Email Security version 10.0.9.x. An unauthenticated remote attacker can trigger it by sending a crafted HTTP request to the vulnerable host, which allows the attacker to create a new administrative account on the Email Security instance. That administrative access gives an attacker full control over the email security platform (CVSS 9.8 with high confidentiality, integrity, and availability impact), enabling persistence, manipulation of email filtering, and a foothold from which to target downstream mail infrastructure. Any organization running SonicWall Email Security 10.0.9.x is affected, whether on hardware appliances (3300, 4300, 5050, 7050, 8300, 9000, 5000, 7000), as a virtual appliance, or via the hosted service. The flaw is being actively exploited in the wild: it was added to CISA's KEV on 2021-11-03 with known ransomware use (headlines tie SonicWall email appliance attacks to the HelloKitty gang), and EPSS estimates an 83.4% probability of exploitation within 30 days (100th percentile).

Do: Upgrade SonicWall Email Security from 10.0.9.x to the latest patched release per SonicWall's instructions, as required by CISA KEV. Audit the deployment for unrecognized administrative accounts created by attackers, review management-interface HTTP logs for suspicious requests, and restrict exposure of the management interface to trusted networks. Because this bug was one of three SonicWall zero-days actively exploited with known ransomware use (HelloKitty), also hunt for signs of compromise and follow-on ransomware activity.

SonicWall SMA 100 series secure remote-access appliances contain an unauthenticated stack-based buffer overflow (CWE-121) in the appliance's network-facing interface, triggered by crafted requests sent to the device without any credentials. A remote attacker who triggers the overflow can execute arbitrary code on the appliance with the privileges of the affected service, gaining a foothold on an internet-facing VPN gateway that typically sits at the network edge. Any organization running an SMA 100 series appliance is affected, and because these appliances provide remote access to corporate networks, compromise can expose entire internal environments. Exploitation is confirmed in the wild: the flaw was added to CISA KEV on 2022-01-28 with known ransomware use, and EPSS assigns a 99.9% probability of exploitation within 30 days (100th percentile). No public proof-of-concept is catalogued in the provided data, but the KEV listing and EPSS score indicate active attacker interest.

Do: Upgrade SMA 100 series appliances to firmware 10.0.7.2 or later per SonicWall's instructions, as required by the CISA KEV listing. Until patched, restrict internet exposure of the SMA portal and management interface to trusted sources where feasible. Because ransomware operators are known to exploit this flaw, review appliance logs for signs of compromise and monitor for unexpected account creation or traffic after patching.

CVE-2021-26084 is an OGNL injection vulnerability (CWE-917) in Atlassian Confluence Server and Data Center that may allow an unauthenticated attacker to execute arbitrary code. Any organization running Confluence Server or Data Center is potentially affected. It is significant because it is listed in CISA's Known Exploited Vulnerabilities catalog with known ransomware use, and EPSS assigns a 100.0% probability of exploitation within 30 days (100th percentile).

Do: Apply updates to Confluence Server and Data Center per Atlassian's instructions, which is the required action in the CISA KEV listing. Prioritize remediation given confirmed in-the-wild exploitation and known ransomware use.

CVE-2021-26855 is a server-side request forgery flaw (CWE-918) in Microsoft Exchange Server that allows an unauthenticated remote attacker to send specially crafted HTTP requests and have the Exchange server process them as itself, disclosing sensitive session information. When chained with sibling Exchange flaws (the 'ProxyLogon' chain), it yields authentication bypass and arbitrary file write, escalating to full remote code execution with SYSTEM-level privileges on the on-premises Exchange server. Any organization running an affected on-premises Exchange server reachable over HTTP/HTTPS (typically outbound webmail) is exposed; Exchange Online was not affected. Exploitation is confirmed in the wild at large scale: the flaw was mass-exploited beginning in early 2021 (notably by the HAFNIUM group), is on the CISA KEV with documented ransomware use, and has a maximum EPSS score of 100% (100th percentile), despite no public PoC listing.

Do: Apply the vendor's March 2021 Exchange security updates (or later cumulative updates) immediately, per the CISA required action; until patched, limit Exchange (ECP/OWA) exposure to the internet via firewall/VPN rules. Hunt for compromise: review IIS logs for unrecognized authenticated activity against FrontEnd HttpProxy endpoints, and check for malicious files or webshells under inetpub\wwwroot\aspnet_client, given the known ransomware use.

CVE-2021-31207 is a security feature bypass in Microsoft Exchange Server, classified as an unrestricted file-write issue (CWE-434) that lets an attacker bypass intended restrictions and write files of their choosing to the server. It is the final bug in the ProxyShell chain: chained with the autodiscover SSRF and PowerShell backend elevation flaws, it allows an unauthenticated attacker to reach the Exchange PowerShell API, write arbitrary files such as an ASPX webshell, and execute code with SYSTEM privileges. A successful attacker gains full control of the on-premises Exchange server, including mailbox access, stolen credentials, and a foothold for lateral movement; the bug has been used to deploy ransomware and keyloggers. On-premises deployments of Microsoft Exchange Server (2013, 2016, and 2019 per vendor advisories) are affected, while Exchange Online/cloud mailboxes are not. Exploitation is essentially certain and ongoing: the flaw is in CISA's KEV (added 2021-11-03) with known ransomware use, public ProxyShell PoC/exploit code is available, and EPSS puts the 30-day exploitation probability at 99.8%.

Do: Apply Microsoft's July 2021 security updates for Exchange Server 2013, 2016, and 2019 (or any later security/cumulative update) per vendor instructions, and restrict untrusted access to Exchange's autodiscover and PowerShell endpoints. Hunt for ASPX webshells under the Exchange FrontEnd directories and review IIS logs for autodiscover.json requests chaining PowerShell, since many servers were compromised before patching. Given known ransomware use and KEV listing, treat any server that was unpatched or internet-exposed during the exploitation window as potentially compromised.

Microsoft Exchange Server contains a server-side request forgery (SSRF, CWE-918) in the Autodiscover service that unauthenticated remote attackers can reach over HTTP. This flaw is the first stage of the widely documented 'ProxyShell' chain, in which the SSRF is combined with privilege escalation and an arbitrary file write in the Exchange PowerShell backend to achieve unauthenticated remote code execution on the server. An attacker who successfully exploits it gains the ability to run code on the Exchange server, and ransomware operators (e.g., Cuba ransomware) leveraged this chain to deploy payloads. Organizations running on-premises Microsoft Exchange Server (2013, 2016, and 2019 per the vendor's advisories) are affected; hosted Exchange Online is a separately managed cloud service. Exploitation is confirmed in the wild: CISA added the flaw to the KEV catalog on 2021-11-03 with known ransomware use, and EPSS assigns it a 100% probability of exploitation within 30 days (100th percentile).

Do: Apply Microsoft's July 2021 (or later) Exchange Server security updates, which include the ProxyShell fixes, to all on-premises servers. If patching is delayed, restrict internet access to the Autodiscover/EWS frontend endpoints and consider the URL Rewrite mitigation Microsoft published for ProxyShell. Given the KEV listing and known ransomware use, treat internet-facing, unpatched Exchange servers as potentially compromised and hunt for webshells, unusual Exchange processes, and suspicious account or mailbox activity.

CVE-2021-40539 is a critical (CVSS 9.8) authentication bypass in the REST API of Zoho ManageEngine ADSelfService Plus, caused by use of an incorrectly resolved name or reference (CWE-706). An unauthenticated, network-adjacent or internet-reachable attacker sends specially crafted requests to the product's REST API, bypassing authentication, and can chain the bypass to full remote code execution with no privileges or user interaction required. Successful exploitation yields complete compromise of the self-service portal server (high impact to confidentiality, integrity and availability); public reporting and vendor notes document attackers dropping malicious code and web shells onto vulnerable servers. Any organization running ManageEngine ADSelfService Plus build 6113 or earlier is affected, which typically means enterprise Microsoft Active Directory environments running this widely deployed self-service password/SSO portal. Exploitation is confirmed in the wild: the flaw was added to CISA KEV on 2021-11-03 with known ransomware use, EPSS puts the 30-day exploitation probability at 99% (100th percentile), Microsoft warned that Chinese threat actors were actively exploiting it, a public proof-of-concept is available, and it ranked among CISA's most routinely exploited vulnerabilities.

Do: Immediately upgrade ManageEngine ADSelfService Plus to a fixed build newer than 6113 per the vendor's update instructions, as required by CISA. Because exploitation predates patching and the flaw has been used to drop malicious code, check ADSelfService Plus servers for web shells, unexpected scheduled tasks, and unexplained accounts/processes, and hunt for indicators from the published analyses. Where possible, restrict internet exposure of the ADSelfService Plus REST API while patching, prioritized for externally reachable instances.

F5 BIG-IP contains a critical missing-authentication flaw (CWE-306) in its iControl REST control plane: an unauthenticated attacker with network reachability to the management interface, or to self IPs exposing the REST service on TCP 443, can bypass authentication completely. By sending specially crafted HTTP requests, the attacker gains the ability to execute arbitrary code, create or delete files, and disable services, effectively achieving full takeover of the load balancer or security appliance and the traffic it handles. All F5 BIG-IP deployments running unpatched software are affected; the provided data does not enumerate exact version ranges, which are listed in F5's May 2022 security advisory. The flaw was added to CISA's KEV catalog on 2022-05-10 with known ransomware use, and EPSS assigns a 100% probability of exploitation within 30 days (100th percentile), indicating active in-the-wild exploitation. No public proof-of-concept is catalogued in the provided data, but the KEV listing and known ransomware use confirm real-world attacks.

Do: Upgrade affected F5 BIG-IP systems to the fixed releases listed in F5's May 2022 security advisory (K23605340) immediately, prioritizing appliances whose management interface or self IPs on TCP 443 are reachable from untrusted networks; as an interim mitigation, block untrusted access to the management interface and the iControl REST service. Because this flaw is in CISA's KEV catalog with known ransomware use, also hunt for signs of compromise (unexpected files, disabled services, unknown persistence) on any system that was exposed before patching.

CVE-2022-22954 is a server-side template injection vulnerability (CWE-94) in VMware Workspace ONE Access and VMware Identity Manager that allows remote code execution on affected appliances. It is triggered when attacker-controlled input is passed into a server-side template engine, allowing injected template directives to be evaluated and executed as code on the server. A successful attacker gains the ability to run arbitrary code on the identity appliance, and CISA notes the flaw has been used in ransomware campaigns, so compromise can serve as an initial foothold for broader enterprise intrusion. Any organization running Workspace ONE Access or Identity Manager, including deployments where the Identity Manager component is bundled into VMware Horizon environments, is potentially affected, though the source data does not specify affected version ranges. The vulnerability was added to CISA's Known Exploited Vulnerabilities catalog on 2022-04-14 with ransomware use confirmed and a required action to apply vendor updates, and EPSS currently assigns it a 100% probability of exploitation within 30 days (100th percentile); no public PoC is known.

Do: Apply the patches published in VMware advisory VMSA-2022-0011 (April 2022) to Workspace ONE Access and Identity Manager appliances as required by the CISA KEV listing, prioritizing internet-facing instances, and restrict or remove public exposure until patched. Review appliance and web-server logs for template-injection probes and unexpected processes spawned by the identity service, and investigate any indications of compromise for follow-on ransomware or lateral-movement activity.

VMware Workspace ONE Access, VMware Identity Manager and vRealize Automation virtual appliances contain a local privilege escalation flaw (CWE-250, execution with unnecessary privileges): support scripts shipped with the appliances have improperly set permissions and run with elevated privileges. An attacker who already has some form of local or shell access to an affected appliance can modify or abuse these scripts to execute code as root (per VMware's advisory), gaining full control of the appliance, its identity/directory data and a platform for persistence and pivoting. Organizations running these VMware identity- and cloud-automation appliances are affected, since the weakness is in the appliance software itself; risk is highest where the appliances are reachable or where this bug is chained with other recently disclosed VMware appliance vulnerabilities. The flaw is known exploited in the wild: it was added to CISA's Known Exploited Vulnerabilities catalog on 2022-04-15, and EPSS assigns a high 35.8% probability of exploitation within 30 days (98th percentile), although no public PoC is known and ransomware use is unconfirmed.

Do: Apply the patched appliance releases per VMware's instructions, as required by CISA's KEV listing; until patched, restrict local, shell and management-plane access to Workspace ONE Access, Identity Manager and vRealize Automation appliances, and review them for unexpected root-level activity or modified support scripts. Treat this as actively exploited and prioritize patching alongside the other flaws fixed in the same VMware advisory.

Atlassian Confluence Server and Data Center contain an unauthenticated remote code execution flaw caused by improper neutralization of expression-language (OGNL) input (CWE-917): an attacker with network access to the application can submit a crafted request that is evaluated as an expression and executed by the server. Successful exploitation lets a remote, unauthenticated attacker run arbitrary code with the privileges of the Confluence process, without any credentials. All organizations running self-managed Confluence Server or Data Center are affected, particularly instances exposed to the internet; Confluence Cloud is not listed among the affected products. Exploitation is confirmed in the wild: the flaw was added to CISA's KEV on 2022-06-02 with ransomware use marked as known, and EPSS assigns a 100% probability of exploitation within 30 days (100th percentile). CVSS has not yet been scored in this data, but the KEV listing and known ransomware use make unpatched, internet-facing instances a top-priority patching target.

Do: Immediately upgrade to the patched Confluence release specified in Atlassian's 2022-06-02 security advisory, and until patched follow the CISA required action to block all internet traffic to and from affected instances. Because in-the-wild exploitation and ransomware use are confirmed, also hunt for compromise indicators on both patched and unpatched hosts, such as webshells, unexpected child processes of the Confluence service, and unusual outbound connections.

CVE-2022-27593 is a critical (CVSS 9.1) externally controlled reference to a resource (CWE-610, an SSRF-style flaw) in the Photo Station photo-sharing application for QNAP NAS devices running QTS. Because the flaw is reachable over the network with no privileges or user interaction required, an unauthenticated attacker who can reach a Photo Station instance can force the application to reference attacker-controlled resources and modify system files. This is the vulnerability the DeadBolt ransomware operation exploited to compromise and encrypt thousands of internet-facing QNAP NAS devices in 2022. Any QNAP NAS running vulnerable Photo Station versions across QTS 4.2.x through 5.x is affected. Exploitation is confirmed in the wild: CISA added the flaw to its Known Exploited Vulnerabilities Catalog on 2022-09-08, ransomware use is known, and EPSS puts the 30-day exploitation probability at 87.9% (100th percentile), though no public PoC is known.

Do: Upgrade Photo Station to the fixed version for your QTS branch: 6.1.2+ on QTS 5.0.1, 6.0.22+ on QTS 5.0.0/4.5.x, 5.7.18+ on QTS 4.3.6, 5.4.15+ on QTS 4.3.3, and 5.2.14+ on QTS 4.2.6. If patching is not immediately possible, disable Photo Station or remove it from internet exposure, since the flaw requires no authentication. Check devices for DeadBolt compromise (encrypted files and ransom notes) and apply updates per CISA's KEV required action and QNAP's instructions.

CVE-2022-30190 (Follina) is a remote code execution flaw in the Microsoft Windows Support Diagnostic Tool (MSDT) when MSDT is invoked through its ms-msdt URL protocol by a calling application such as Microsoft Word. Attackers trigger it by luring a user into opening a malicious document — typically a Word/RTF file whose link or remotely linked template launches the ms-msdt: URI with attacker-supplied commands — and CVSS 3.1 rates it 7.8 with a local attack vector and required user interaction. A successful exploit runs arbitrary code with the privileges of the calling application, allowing the attacker to install programs, view, change or delete data, or create new accounts in the user's context. Per the CISA data, affected platforms are Windows 7, 8.1 and RT 8.1, Windows 10 versions 1507 through 21H2, Windows 11 21H2, and Windows Server 2008 and 2012 — essentially any Windows installation that ships MSDT, with Office/Word as the common delivery vector. Exploitation is confirmed in the wild: Microsoft acknowledged it as an exploited zero-day, CISA added it to the KEV on 2022-06-14 with known ransomware use, EPSS puts the 30-day exploitation probability at 99.2% (99th percentile), and contemporaneous reporting also tied its use to espionage actors including APT28.

Do: Apply Microsoft's security updates per vendor instructions (the fix shipped in the June 2022 Patch Tuesday releases for the affected Windows versions), as required by CISA's KEV. If patching must be delayed, follow Microsoft's documented mitigation to disable the MSDT URL protocol (remove or restrict the HKEY_CLASSES_ROOT\ms-msdt registry key) and enforce Office Protected View / block Word from fetching remote templates over the network. Hunt for exploitation by checking whether Office processes (WINWORD.exe) launch msdt.exe or sdiagnhost.exe, or whether ms-msdt: URIs are invoked unexpectedly.

Fortinet's FortiOS, FortiProxy, and FortiSwitchManager contain an authentication bypass vulnerability (CWE-288) that lets an unauthenticated remote attacker gain access to the administrative interface. It is triggered by sending specially crafted HTTP or HTTPS requests directly to the admin interface, with no credentials or exploit code required. By bypassing authentication, an attacker can perform administrative operations on the device, such as modifying configuration or creating privileged accounts. Any organization running the affected products is exposed, particularly where the management interface is reachable from the internet. The flaw is being actively exploited: it was added to CISA's Known Exploited Vulnerabilities catalog on 2022-10-11 with known ransomware use, and EPSS assigns it roughly a 100% probability of exploitation within 30 days, although no public PoC is known.

Do: Upgrade FortiOS, FortiProxy, and FortiSwitchManager to the fixed releases identified in Fortinet's advisory per the KEV required action. As mitigation, restrict access to the admin interface (e.g., disable WAN-facing management and use local-in policies or allow-lists for management IPs). Review admin logs and device configuration for signs of unauthorized access, such as unexpected admin accounts, added SSH keys, or config changes.

CVE-2022-41082, dubbed "ProxyNotShell," is an authenticated remote code execution vulnerability in Microsoft Exchange Server; the associated CWE-502 indicates deserialization of untrusted data. It is exploited in a chain with CVE-2022-41040, a server-side request forgery in Exchange that lets an unauthenticated attacker reach the vulnerable endpoint via crafted web requests and trigger the remote code execution. Successful exploitation gives an attacker the ability to run code on the Exchange server, and CISA notes known ransomware use. Any organization running an on-premises Microsoft Exchange Server deployment is potentially affected, with the specific version ranges per Microsoft's advisory. The flaw is actively exploited in the wild: it was added to CISA KEV on 2022-09-30 with ransomware use known, and EPSS assigns a 100% probability of exploitation within 30 days, even though no public proof-of-concept is known.

Do: Apply Microsoft's Exchange security updates immediately per vendor instructions, as required by CISA's KEV listing (added 2022-09-30). If patching is delayed, apply Microsoft's interim mitigations that restrict access to the Autodiscover endpoint used in the CVE-2022-41040 SSRF chain, and review web and PowerShell logs for signs of compromise given the known ransomware use.

CVE-2022-42475 is a critical (CVSS 9.8) heap-based buffer overflow in the SSL-VPN service of Fortinet FortiOS and FortiProxy. A remote, unauthenticated attacker can trigger it by sending specifically crafted requests to an exposed SSL-VPN interface, with no user interaction or credentials required. Successful exploitation yields arbitrary code or command execution on the appliance, giving attackers a foothold on the perimeter device from which they can pivot into internal networks. Any organization running the listed FortiOS (6.0 through 7.2) or FortiProxy (7.0/7.2) versions with SSL-VPN enabled is affected. Exploitation is confirmed in the wild: the flaw is in CISA KEV with known ransomware use, has near-certain exploitation probability (EPSS 99.5%), and has been used in targeted government attacks and a Chinese-nexus espionage campaign that compromised over 20,000 systems, with attackers also noted to retain access even after patching.

Do: Upgrade FortiOS and FortiProxy to fixed releases per Fortinet advisory FG-IR-22-398 (any version beyond the listed affected ranges), and reboot the appliance after patching to clear lingering SSL-VPN sessions since attackers have been observed retaining access post-patch. Check for indicators of compromise such as unknown local accounts, unexpected processes, and anomalous historical logins, and rotate SSL-VPN credentials if compromise is suspected. If SSL-VPN is not required, disable it or restrict exposure to trusted sources until patched.