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ConnectWise Patches ScreenConnect Vulnerability Exploited in Worm-Like Attacks

ConnectWise patched critical ScreenConnect flaw CVE-2026-84869 (CVSS 9.9) exploited since August 20 in worm-like attacks; CISA added it to KEV.

ConnectWise released urgent patches for CVE-2026-84869 (CVSS 9.9), a missing authorization and improper privilege management flaw in ScreenConnect allowing file transfer and execution through active remote sessions without host confirmation. Huntress reported in-the-wild exploitation since August 20, with attackers using rogue ScreenConnect clients to push four VBScript files for persistence and worm-like propagation to other ScreenConnect clients. The flaw is fixed in ScreenConnect 26.6.5, with disabling the TransferFiles permission as a temporary mitigation. CISA added the CVE to its KEV catalog, requiring federal agencies to patch within three days under BOD 26-04.

SecurityWeekupdated · 5h agofirst · 2d agoExploit / PoC in the wild 4 sourcesCVE-2026-848691

Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software IKEv2 Certificate Authentication Denial of Service Vulnerability

Cisco patched an ASA/FTD IKEv2 certificate authentication flaw letting unauthenticated remote attackers crash the IKEv2 process and reload devices with crafted certificates.

A logic error during the certificate authentication phase of IKEv2 connection setup in Cisco Secure Firewall ASA and FTD Software allows an unauthenticated, remote attacker to crash the IKEv2 process. Exploitation involves attempting to establish an IKEv2 VPN connection with a crafted certificate, causing a denial of service through an unexpected device reload. Cisco has released software updates.

CVE-2026-78336: Apache Syncope: OIDCC4UI provider list discloses client secrets to any authenticated user

Apache Syncope's OIDCC4UI extension leaks OIDC client secrets in the provider list to any authenticated user, versions through 4.1.2 affected.

CVE-2026-78336 is a moderate-severity insertion-of-sensitive-information-into-sent-data flaw in Apache Syncope's syncope-ext-oidcc4ui-logic module. The OIDCC4UI provider list discloses client secrets to any authenticated user. Affected versions are 3.0.0-M0 through 3.0.16, 4.0.0-M0 through 4.0.7, and 4.1.0-M0 through 4.1.2.

oss-security · 2d agoVulnerabilityCVE-2026-783361

Certificate Transparency Monitoring is now generally available

Cloudflare's Certificate Transparency Monitoring is now generally available, and it no longer alerts on certificates Cloudflare issued for your own domains.

Cloudflare announced general availability of its Certificate Transparency Monitoring service. The key behavioral change is that alerts are no longer generated for certificates that Cloudflare itself issued for a customer's domains, so any alert received now indicates a certificate issued by another certificate authority. Defenders can use the service to detect mis-issued or unauthorized TLS certificates for their domains.

Cloudflare Blog · Aug 13, 2026Tools

ZTNA Portal Improper Certificate Validation

Fortinet fixed an improper certificate validation flaw (CVSS 7.3) in FortiOS and FortiProxy Agentless ZTNA portal enabling unauthenticated man-in-the-middle attacks on backend traffic.

Fortinet advisory FG-IR-26-174 discloses an improper certificate validation vulnerability (CWE-295) in the FortiOS and FortiProxy Agentless ZTNA portal, rated CVSSv3 7.3. A remote and unauthenticated attacker can perform a man-in-the-middle attack on the communication channel between the ZTNA portal and the backend destination website. The advisory was revised on 2026-09-08.

Fortinet PSIRT · 8d agoAdvisory

CVE-2026-74761: Apache ActiveMQ Broker, Apache ActiveMQ All, Apache ActiveMQ: Spoofing of RemoveSubscription clientId

Apache ActiveMQ CVE-2026-74761: moderate clientId spoofing in RemoveSubscription handling, affecting Broker, All and apache-activemq, fixed in 6.3.2 and 5.19.11.

The Apache ActiveMQ team disclosed CVE-2026-74761, a moderate-severity spoofing issue in the handling of RemoveSubscription clientId. Affected components include ActiveMQ Broker (activemq-broker), ActiveMQ All (activemq-all) and Apache ActiveMQ in versions 6.0.0 before 6.3.2 and 5.x before 5.19.11. The flaw could allow a client to spoof another client's clientId when removing subscriptions. Users should upgrade to the 6.3.2 or 5.19.11 release lines or later.

oss-security · 8d agoVulnerabilityCVE-2026-747611

Windows Remote Desktop Client Vulnerability Allows Attackers to Execute Remote Code

Microsoft patched CVE-2026-69485, an 8.8 CVSS RCE flaw in the Windows Remote Desktop Client affecting Windows 10/11 and Server 2016-2025.

Microsoft's September 2026 updates fix CVE-2026-69485, an Important-rated remote code execution vulnerability (CVSS 3.1: 8.8, temporal 7.7) in the Windows Remote Desktop Client caused by use of an uninitialized resource. An authenticated attacker with low privileges could send a specially crafted network request to execute code on an affected server, with no user interaction required. Microsoft says the flaw was not publicly disclosed before patching and rates exploitation as 'Less Likely' with no evidence of active exploitation. Affected products span Windows Server 2016, 2019, 2022 and 2025 and Windows 10 (1607-22H2) and Windows 11 (23H2-26H1), with fixes delivered via KBs including KB5123099, KB5122876 and KB5122882.

Cisco BroadWorks Out-of-Band Blind XML External Entity Injection Vulnerability

Cisco patched an XXE flaw in BroadWorks' OCI XML parser letting unauthenticated remote attackers read sensitive files from the filesystem.

Cisco BroadWorks permits external entity resolution by default in its Open Client Interface XML parser, enabling out-of-band blind XXE injection. An unauthenticated remote attacker can send crafted XML to the OCI-P provisioning service and read sensitive configuration files with BroadWorks user privileges. Cisco has released software updates and no workarounds are available.

Cisco Security Advisories · 28d agoAdvisory

VU#431093: TCG TPM 2.0 reference code found vulnerable to information leakage and timing side-channel attacks

CERT/CC discloses two TPM 2.0 reference code flaws allowing RSA key decryption and forged TPM attestations via crafted commands.

CERT/CC published VU#431093 covering two vulnerabilities in the TCG TPM 2.0 reference implementation: CVE-2026-6726 (information leakage via falsified TPM keys) and CVE-2026-6727 (timing side-channel in RSA OAEP decryption). An attacker with privileged access to a TPM command interface could send crafted TPM commands to decrypt ciphertexts for affected TPM-managed RSA keys, including the RSA Endorsement Key, or obtain credentials enabling forged TPM 2.0 attestations. Remediation is tracked in TCGVRT010 and TCGVRT0011.

CVE-2026-77181: Apache Syncope: ClientApp update entitlement not effective

Apache Syncope discloses low-severity CVE-2026-77181, an incorrect authorization flaw where the ClientApp update entitlement is not effective in versions 3.0.x through 4.1.2.

Francesco Chicchiriccò posted a low-severity advisory for CVE-2026-77181, an Incorrect Authorization vulnerability in Apache Syncope's syncope-core-am-logic module. Affected versions include 3.0.0-M0 through 3.0.16, 4.0.0-M0 through 4.0.7, and 4.1.0-M0 through 4.1.2. An administrator holding the ClientApp update entitlement finds it is not applied as expected. No exploitation is reported and the issue is rated low severity.

oss-security · 2d agoVulnerabilityCVE-2026-77181

Citrix urges customers to fix critical NetScaler authentication bypass (CVE-2026-19490)

Citrix patched a critical authentication bypass, CVE-2026-19490, in NetScaler Gateway and NetScaler ADC, urging customers to upgrade immediately.

Citrix has patched two flaws in NetScaler ADC and NetScaler Gateway. CVE-2026-19490 is a critical authentication bypass (CVSS v4.0 9.3) that works when the appliance is configured as an SSL VPN, ICA Proxy, CVPN, RDP Proxy Gateway or AAA virtual server, with additional conditions depending on firmware and SAML configuration. A second flaw, CVE-2026-19489 (CVSS 8.8), is a memory overflow that can cause denial of service when SIP ALG is enabled on LSN setups. Rapid7 had not observed exploitation as of August 19, 2026, but urged emergency patching; a signature-based mitigation is available via NetScaler Console.

Certificate failures can cost firms over $250,000

DigiCert survey finds certificate failures cost firms over $250,000 per incident, with 47-day TLS certificates set to multiply management workloads by 2029.

DigiCert's Certificate Management Outlook reports that 34% of companies experienced outages from expired certificates and 40% from mismanagement, with nearly one in four citing incidents costing over $250,000. The CA/Browser Forum's move to 47-day certificate lifespans by 2029 will require renewals eight times more often and 40 times as many domain validations. Over half of organizations manage more than 1,000 certificates, yet only 10% have automation in place, with budget constraints and legacy systems cited as key barriers.

Help Net Security · 2d agoIndustry

Modified ScreenConnect Clients Used in Worm-Like Campaign

Huntress warns of worm-like attacks using modified ScreenConnect clients to spread VBScript payloads; ConnectWise issued an advisory.

Campaigns starting in late August use social engineering, including Quick Assist abuse, to install rogue ScreenConnect clients that spawn wscript.exe and deploy four VBScript files for reconnaissance, staging, and PowerShell execution. The attackers persist via User Run Keys, attempt UAC bypass, install UltraViewer, and propagate the VBScript chain to other connected ScreenConnect endpoints. ConnectWise published an advisory about a file transfer behavior issue affecting cloud and on-premises ScreenConnect, with a CVE identifier and fix expected within a week; it recommends disabling file transfer meanwhile.

SecurityWeek · 9d agoExploit / PoC in the wild

Wärtsilä FOS-Onboard

CISA advisory: two hardcoded cryptographic key flaws in Wärtsilä FOS-Onboard 5.07.0923.01 (CVSS 9.0/9.1) could allow unauthorized updates, code execution, and credential theft.

CISA advisory ICSA-26-258-02 discloses CVE-2026-78225 (CVSS 3.1 9.0 critical), a hardcoded cryptographic server key in the deployer-ng Update Controller of Wärtsilä FOS-Onboard 5.07.0923.01. CVE-2026-81855 (CVSS 3.1 9.1 critical) is a hardcoded client authentication key in the robot testing framework component. Successful exploitation could let an attacker deliver unauthorized updates, execute code, or extract credentials to impersonate a privileged client. The product is deployed worldwide in transportation systems critical infrastructure; Cydome Security reported the flaws and CISA states no known public exploitation exists.

Session Attestation for Unmodified TLS Services in Confidential Virtual Machines

SessionLatch adds session attestation to unmodified TLS services in confidential VMs, cutting short-upload latency 63.1% versus TNG on Hygon CSV.

SessionLatch provides session attestation for confidential virtual machines without modifying applications, TLS implementations, or certificates. It relies on trusted observation of the server's locally generated ephemeral public key combined with standard TLS key confirmation, moving attestation integration to the operating system via a temporary latch that overlaps evidence exchange with the TLS handshake. Implemented with Linux and Windows integrations and evaluated on real Hygon CSV attestation, it reduces short-upload mean latency by 63.1%/23.0% relative to TNG in interleaved Linux/Windows experiments, while preserving enterprise service authentication and the native TLS data path, and supports mutual attestation.

arXiv cs.CR · 7d agoResearch

You’re Back In The Room (Citrix NetScaler Pre-Auth RCE CVE-2026-8452(?))

watchTowr Labs details a pre-authentication remote code execution flaw, tracked as CVE-2026-8452, in Citrix NetScaler appliances.

watchTowr Labs published technical analysis of a pre-authentication remote code execution vulnerability in Citrix NetScaler, tentatively assigned CVE-2026-8452. The CVE identifier is marked as provisional in the write-up. No confirmation of in-the-wild exploitation is provided in the available text.

watchTowr Labs · Aug 14, 2026Exploit / PoCCVE-2026-8452

[0day-rubbish] DBxtra .NET 13.1.1.0 Unauthenticated SOAP API to xp_cmdshell code execution (9.8)

0day Rubbish disclosed an unauthenticated SOAP API flaw in DBxtra .NET 13.1.1.0 enabling xp_cmdshell command execution, rated CVSS 9.8.

The 0day Rubbish Research Team disclosed an unauthenticated remote code execution vulnerability in DBxtra .NET 13.1.1.0, classified as CWE-306 (missing authentication). The flaw is reachable via the unauthenticated SOAP API and abuses SQL Server's xp_cmdshell to run operating system commands. It is rated CVSS 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H). No CVE identifier or exploitation evidence was provided in the disclosure.

Full Disclosure · 8d agoVulnerability 2 sources

FreeIPA Flaw Chain Lets Anonymous Clients Create Reusable Administrator Credentials

Critical FreeIPA flaw chain (CVE-2026-76578, CVSS 9.8) lets anonymous clients create reusable admin credentials on default installs; fixed in 4.13.4.

Red Hat warns that chaining FreeIPA's CVE-2026-76578 (CVSS 9.8) with a 389 Directory Server flaw (CVE-2026-76560, CVSS 7.5) lets an anonymous client write a Kerberos identity into the directory and land in the administrators group on default installations; Red Hat reproduced the chain twice, including on a machine with no access at all. FreeIPA 4.13.4 fixes both flaws, and fourteen 389-ds advisories shipped September 8, with RHSA-2026:64785 rated critical. A separate flaw, CVE-2026-79678 (CVSS 8.1), allows reading the server's environment variables one at a time via a Python eval() in idp-add, potentially exposing Directory Manager and administrator passwords in container installs. No real-world exploitation has been reported.

Securing Claude Code: The New Compliance API, Local Visibility, and Identity Governance

Anthropic's new Compliance API endpoints expose Claude Code local session transcripts, highlighting governance gaps for endpoint AI agents.

Anthropic added local session transcript endpoints to its Compliance API on August 11, 2026, giving security teams visibility into prompts, bash commands, file operations, and MCP commands run by Claude Code harnesses on endpoints. The article argues local harnesses break the classic shared-responsibility model, citing Token Security data that 68.6% of discovered AI agents run on endpoints, and a Cloud Security Alliance survey of 418 IT and security professionals in which 82% found an unknown agent within the past year. It outlines three governance layers: Anthropic managed settings as a policy baseline, the Compliance API for cloud-visible transcripts, and endpoint telemetry to connect agent activity to identity, credentials, and permissions.

The Hacker News · 16d agoAI safety & security1

Siemens Teamcenter

Reflected XSS in Siemens Teamcenter /auth/ redirect flow lets unauthenticated attackers inject JavaScript into authenticated sessions (CVE-2026-58113).

CISA republished Siemens advisory SSA-157465 for CVE-2026-58113, a reflected cross-site scripting flaw (CVSS 6.1) in the /auth/ authentication redirect flow of Siemens Teamcenter V2412, V2506, V2512, and V2606. An unauthenticated attacker can craft a URL that injects arbitrary JavaScript into an authenticated user's browser, enabling data theft or actions within the victim's Teamcenter session. Fixed versions are available for all affected releases; Enzo Alvarez of Bishop Fox reported the vulnerability.

CISA Advisories · 1d agoAdvisoryCVE-2026-58113

Server-Side Request Forgery (SSRF)

Fortinet discloses a low-severity SSRF in the FortiSIEM GUI allowing authenticated attackers to send requests from targeted devices.

Fortinet PSIRT advisory FG-IR-26-159, revised 2026-08-12, describes a server-side request forgery (CWE-918) in the FortiSIEM GUI, scored CVSSv3 3.4. An authenticated attacker can send HTTP requests originating from the targeted device via specially crafted requests, potentially enabling internal network probing. No CVE identifier or exploitation status is included in the advisory text.

Fortinet PSIRT · Aug 12, 2026Advisory

Attackers use rogue ScreenConnect clients to spread malware

Attackers deploy rogue ScreenConnect clients that spread VBScript malware to newly connected machines while ConnectWise patches a file-transfer flaw.

ConnectWise confirmed a file transfer flaw in ScreenConnect affecting both Cloud and On-Premise deployments, with a CVE identifier and official fix promised within the week; administrators can mitigate immediately by disabling TransferFiles (or TransferFilesInSession) in each role. Huntress documented incidents where social engineering installs rogue ScreenConnect clients that spawn Windows Script Host processes running four VBScript files (1.vbs-4.vbs), add a WindowsServiceHost registry Run key, and propagate to newly connected endpoints. Payloads enabled host profiling, persistence, additional ScreenConnect installs, tunneling, security-control changes, and cryptocurrency mining. ConnectWise has not confirmed a technical link between the flaw and this campaign.

Help Net Security · 9d agoExploit / PoC in the wild

Accountability in Certificate Transparency and Variants

Formal Dolev-Yao analysis shows plain Certificate Transparency requires an honest log, SCT Auditing removes that assumption, and Gossiping does not.

The paper analyzes accountability in Certificate Transparency and its SCT Auditing and Gossiping extensions in the Dolev-Yao model, starting from a vanilla PKI. It finds plain CT provides accountability only under the assumption of an honest log. The SCT Auditing extension can eliminate that assumption, while the Gossiping extension cannot. CT is supported by all major browsers and obliges Certificate Authorities to record issued certificates in public, monitored logs.

arXiv cs.CR · 6d agoResearch

Broken access control in the RADIUS type admin group

FortiWeb RADIUS admin authentication flaw (CVSS 8.8) permits remote GUI/CLI login with random credentials under specific non-default settings.

Fortinet advisory FG-IR-26-158 describes an improper authentication flaw (CWE-287) in FortiWeb's Remote RADIUS-type admin authentication, scored CVSSv3 8.8. When the configuration uses specific non-default settings, a remote unauthenticated attacker can log into the FortiWeb GUI or CLI with a random username and password. The advisory was revised on 2026-08-12 and does not state that exploitation has been observed.

Fortinet PSIRT · Aug 12, 2026Advisory

USN-8670-3: curl vulnerability

Ubuntu issued USN-8670-3 updating curl for Ubuntu 26.04 LTS to fix a flaw where wrong client certificates could be used on reused connections.

Ubuntu Security Notice USN-8670-3 extends the curl fix from USN-8670-1 to Ubuntu 26.04 LTS. The flaw, discovered by Joshua Rogers, involves incorrect handling of connection reuse when client certificate settings change, potentially causing the wrong client certificate to be presented. The issue can lead to authentication mix-ups rather than remote code execution.

Ubuntu Security Notices · 8d agoAdvisory

SAP Patches Critical Extended Passport Processing Vulnerability

SAP patches CVSS 10.0 flaw CVE-2026-44756 (OVERPASS) enabling unauthenticated RCE in S/4HANA and NetWeaver, plus three other criticals; no in-the-wild exploitation reported.

CVE-2026-44756 is a CVSS 10.0 memory corruption flaw in Extended Passport (EPP) deserialization, triggered when a user session opens across web, SAP GUI, and RFC vectors. Exploitation yields command execution as the SAP OS account, database credential and password hash recovery, session reading, and data or binary modification; affected products include S/4HANA, ERP/ECC, NetWeaver, Web Dispatcher, and BW/4HANA. Three other criticals were patched: CVE-2026-58240 (S4GET, missing authentication affecting all S/4HANA 2025 and earlier releases), CVE-2026-76969 (CAP credential disclosure), and CVE-2026-66768 (NetWeaver access control). Onapsis and SAP report no indicators of in-the-wild exploitation.

Cisco Secure Firewall Management Center Software Java Deserialization Remote Code Execution Vulnerability

Cisco fixed an unauthenticated Java deserialization RCE in FMC's External Database Access feature allowing root command execution via a TCP port.

Insecure deserialization of a user-supplied Java byte stream in Cisco Secure Firewall Management Center's External Database Access feature lets an unauthenticated remote attacker execute arbitrary commands and elevate to root. Exploitation requires sending a crafted serialized stream to a specific TCP port from a host configured in the external database access list. Cisco has released software updates.

Jellyfin 12.0 security fixes arrive alongside the removal of legacy client logins

Jellyfin 12.0 ships security fixes for path traversal, first-run setup bypass, unsafe plugin names, and web client XSS, plus removal of legacy login paths.

Jellyfin 12.0 blocks requests built to reach files outside served folders, prevents setup-wizard re-runs on misconfigured servers, rejects unsafe plugin package names, and fixes web client cross-site scripting. The project published no CVE identifiers or severity ratings for the fixes. The release also drops legacy /emby/ and /mediabrowser/ endpoints, targets .NET 10, and breaks 10.11-era third-party plugins.

Help Net Security · 8d agoVulnerability