CISA adds Veeam Backup and Replication bugs to Known Exploited Vulnerabilities Catalog

CVE-2022-26501 is a critical (CVSS 9.8) missing-authentication/incorrect-access-control flaw in Veeam Backup & Replication 10.x and 11.x that allows unauthenticated remote code execution; it is one of two related flaws (CVE-2022-26500 and CVE-2022-26501) fixed together by Veeam. An attacker who can reach the affected backup service over the network can trigger the flaw without any credentials or user interaction and gain code execution with full confidentiality, integrity, and availability impact on the backup server. This hands attackers control of the backup infrastructure itself, which is valuable for harvesting stored credentials, tampering with or destroying backups, and moving laterally ahead of ransomware detonation. Any organization running Veeam Backup & Replication 10.x or 11.x is affected. Exploitation is confirmed in the wild: CISA added it to the Known Exploited Vulnerabilities Catalog on 2022-12-13 with known ransomware use, and public reporting associates these flaws with Cuba ransomware gang activity.

Do: Apply Veeam's updates per vendor instructions to all 10.x and 11.x deployments and verify the patched build is installed on every backup server. Restrict network access to Veeam backup infrastructure (including any internet-exposed or cloud-facing Veeam services) to trusted management networks, and hunt for exploitation indicators given the known ransomware use. Because exploitation is in the wild, treat patching of Veeam backup servers as urgent and high priority.

CVE-2022-27518 is a critical flaw in Citrix Application Delivery Controller (ADC) and Gateway firmware that permits unauthenticated remote arbitrary code execution, which CISA characterizes as an authentication bypass. It is triggered remotely over the network with no credentials, privileges, or user interaction required (CVSS 3.1: AV:N/AC:L/PR:N/UI:N, score 9.8), so any affected appliance with an internet-reachable interface is a potential target. A successful attacker gains code execution on the appliance and access to sensitive resources, which is especially dangerous on VPN gateway and load-balancing deployments that front-door enterprise networks. All organizations running Citrix ADC or Gateway appliances are potentially affected, with internet-exposed devices at greatest risk. The flaw is being actively exploited in the wild, including by state-sponsored actors; it was added to CISA KEV on 2022-12-13 and Citrix and the NSA publicly urged admins to patch, though no public proof-of-concept is known.

Do: Apply the fixed firmware updates per Citrix's vendor instructions immediately, prioritizing internet-facing ADC and Gateway appliances, since the flaw is in CISA KEV and actively exploited by state-sponsored actors. Until patched, restrict or shield appliance interfaces where feasible, and review internet-exposed devices for indicators of compromise given the absence of a public PoC.

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.

CVE-2022-42856 is a type confusion vulnerability (CWE-843) in Apple's WebKit web engine, addressed with improved state handling and affecting Safari, iPhone OS (iOS), iPadOS, macOS (Ventura) and tvOS. It is triggered when a user processes maliciously crafted web content, for example by visiting an attacker-controlled web page, in a WebKit-based browser or app. Successful exploitation may lead to arbitrary code execution on the affected device. Anyone running the affected Apple platforms below the December 2022 patch level (Safari 16.2, macOS Ventura 13.1, tvOS 16.2, iOS/iPadOS 15.7.2, iOS 16.1.2) was exposed, which effectively means most Apple users at the time of disclosure. Exploitation is confirmed: Apple reported the issue may have been actively exploited against iOS versions released before iOS 15.1, it was added to CISA KEV on 2022-12-14 (EPSS 8.5%, 95th percentile), and related reporting ties it to commercial spyware campaigns in Italy, Malaysia, Kazakhstan and the UAE.

Do: Update immediately to Safari 16.2, macOS Ventura 13.1, tvOS 16.2, and iOS/iPadOS 15.7.2 (for iOS 15-era devices) or iOS 16.1.2 (for iOS 16-era devices), or any later release; this is a CISA KEV entry whose required action is to apply vendor updates. Because the flaw was exploited as a zero-day against iOS versions before iOS 15.1 and is linked to commercial spyware campaigns, treat patching as urgent and verify that all managed and BYOD iPhones and iPads are on a fixed version; on iOS, all third-party browsers and most web-content apps use WebKit, so the OS update itself is the remediation rather than switching browsers.

CVE-2022-44698 is a security feature bypass in Microsoft Defender SmartScreen in which specially crafted files do not properly trigger the SmartScreen Mark-of-the-Web warning prompt. The flaw is triggered over the network but requires user interaction: an attacker typically delivers a crafted file via a malicious link or phishing email, and when the user clicks or opens it, SmartScreen fails to show its usual warning. An attacker gains the ability to run malicious content on a user's machine without the standard SmartScreen prompt, making the flaw an effective delivery and initial-access aid — it has documented use in ransomware campaigns. Anyone running the affected Windows releases is exposed: Windows 10 versions 1607 through 22H2, Windows 11 21H2, and Windows Server 2016, 2019, and 2022. The vulnerability was exploited as a zero-day before patching, was added to CISA's Known Exploited Vulnerabilities catalog on 2022-12-13 with known ransomware use, and Google reported a ransomware gang abusing it in the wild.

Do: Apply Microsoft's December 2022 security updates (or any later cumulative updates) for Windows 10, Windows 11, and Windows Server, prioritizing user workstations and systems exposed to phishing or web downloads, per the CISA KEV required action. Until patched, reinforce user awareness that downloaded files may not trigger the usual SmartScreen warning, and consider restricting download or execution of risky file types. Confirm remediation against CISA KEV guidance and treat this as high-priority given known ransomware exploitation.