Active Exploitation Attempts Target WSO2 API Manager JWT Bypass With Forged Admin Tokens
watchTowr observed active exploitation of CVE-2026-5430, a WSO2 API Manager JWT bypass using forged admin tokens, risking credential theft and account takeover.
CVE-2026-5430 (CVSS 9.8-10.0), an improper cryptographic signature verification flaw in WSO2 API Manager, lets JWT authentication be bypassed with unsupported algorithms, enabling administrative account takeover. watchTowr honeypots captured forged JWT tokens with baked-in administrator privileges on September 13, 2026, which could expose API credentials, consumer keys, and secrets for every registered application. Affected products include WSO2 API Manager 4.1.0-4.6.0, API Control Plane, Traffic Manager, and Universal Gateway. Fixes are available via GitHub pull requests and subscription update levels, and users are urged to patch immediately.
CVE-2026-73178: Apache Syncope: JWT Access Token takeover
Apache Syncope discloses CVE-2026-73178, an important-severity flaw enabling JWT access token takeover in versions 3.0.x through 4.1.2.
Apache Syncope disclosed CVE-2026-73178, an Exposure of Sensitive Information to an Unauthorized Actor vulnerability rated important that allows JWT access token takeover. Affected versions include syncope-core-provisioning-java 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. Users should upgrade to the latest fixed releases.
Attackers Exploit Issabel Framework Flaw Enabling Unauthenticated OS Command Executionnew
Attackers actively exploit CVE-2026-89026, a hard-coded JWT key flaw enabling unauthenticated OS command execution on Issabel PBX systems.
VulnCheck reported active exploitation of CVE-2026-89026 (CVSS v3.1 9.8) in Issabel Framework, the web framework for the open-source Issabel unified communications PBX. A hard-coded HS256 JWT signing key identical across every installation lets unauthenticated attackers forge bearer tokens and abuse the /pbxapi/manager/originate endpoint, causing Asterisk to execute arbitrary OS commands as the Asterisk user. A patch replacing the hard-coded key with one stored in /etc/issabel.conf shipped August 1, 2026, and the Shadowserver Foundation first observed exploitation on September 9, 2026. Details on real-world abuse, attribution, and scale remain unknown.
JWT used for authentication in web GUI signed with static key
Fortinet warns that FortiMonitorOnSight's web GUI uses JWTs signed with a static key, enabling remote unauthenticated authentication bypass.
Fortinet advisory FG-IR-26-170 discloses a CVSS 9.6 vulnerability (CWE-540, sensitive information in source code) in the FortiMonitorOnSight web portal. The web GUI's JWT authentication tokens are signed with a static key, allowing a remote unauthenticated attacker to bypass authentication via forged or reused JWTs. The advisory was revised on September 8, 2026.
SharePoint CVE-2026-55040 Comes Under Attack Following Public Exploit
Attackers are actively exploiting critical SharePoint authentication bypass CVE-2026-55040 (CVSS 9.1) days after Rapid7 released a public PoC.
CVE-2026-55040 is a critical authentication bypass (CVSS 9.1) in SharePoint Server Subscription Edition that lets unauthenticated attackers forge JWT tokens and impersonate any user, including administrators. Microsoft patched it in July 2026 Patch Tuesday, but Rapid7 published a technical write-up and Python PoC on GitHub on August 12, and Defused quickly observed attackers running the PoC against SharePoint honeypots. KEVIntel recorded 12 exploitation attempts since July 19, with eight occurring on August 12-13 from IP addresses in Hong Kong, Japan, the Netherlands, Taiwan and the U.S. Admin-level SharePoint access exposes documents and data modification and can serve as a foothold into broader Microsoft 365 infrastructure; unpatched instances should apply the July update immediately.
Rapid7 Analysis: Microsoft SharePoint JWT Token Authentication Bypass (CVE-2026-55040)
Rapid7's analysis of SharePoint auth bypass CVE-2026-55040 includes a PoC for unauthenticated admin-level operations.
Rapid7 and Microsoft disclosed CVE-2026-55040, an authentication bypass in Microsoft SharePoint, on July 14, 2026. The flaw stems from multiple issues in SharePoint's JWT token validation pipeline, allowing a remote unauthenticated attacker to bypass authentication and perform operations as a site user or administrator. Rapid7 has now published a technical analysis and a proof-of-concept script, based on SharePoint Server Subscription Edition.
U.S. CISA adds Apple macOS, Microsoft SharePoint, Broadcom VMware vCenter, and Microsoft IKE flaws to its Known Exploited Vulnerabilities catalog
CISA adds actively exploited flaws in Microsoft IKE, SharePoint, VMware vCenter, and macOS Screen Sharing to KEV catalog, due August 21.
CISA added four vulnerabilities to its Known Exploited Vulnerabilities catalog: CVE-2026-33824 (Windows IKE remote code execution, CVSS 9.8), CVE-2026-55040 (SharePoint JWT authentication bypass, CVSS 9.1), CVE-2026-59310 (VMware vCenter Syslog path traversal, CVSS 9.8), and CVE-2026-65400 (macOS Screen Sharing improper authentication). The SharePoint flaw combines four weaknesses including alg:none JWT forging to impersonate any user, with Defused researchers observing attackers using Rapid7's PoC against honeypots. The Dutch NCSC confirmed active exploitation of the macOS Screen Sharing flaw on August 15, 2026. Federal agencies must patch by August 21, 2026.
Researchers Disclose AI-Assisted SharePoint Exploit Chain Reaching Unauthenticated RCE
Rapid7 disclosed CVE-2026-55040, a SharePoint JWT validation bypass chaining into CVE-2026-63520 unauthenticated RCE, with research substantially AI-agent-assisted; patches released.
Rapid7 disclosed CVE-2026-55040 (CVSS 9.1), several JWT validation pipeline issues letting unauthenticated attackers impersonate chosen SharePoint users by SID or UPN, chained with CVE-2026-63520 (CVSS 8.1), an unsafe .NET type instantiation in Business Connectivity Services yielding RCE as the service account. An AI agent contributed significantly across 96 sessions and roughly 80,000 tool calls over 24 active days, though an expert had to steer it and it repeatedly overstepped its threat model. No exploitation of the bypass had been reported as of CISA's July 14 assessment. The RCE affects SharePoint Subscription Edition, 2019, and 2016, plus Project Server 2013 SP1 and Office Web Apps 2013 SP1; the July updates break the chain.
Artifactory flaws chained in attacks deploying backdoor malware
Attackers chain JFrog Artifactory flaws CVE-2026-42018 and CVE-2026-42016 to gain admin tokens and deploy a Rust backdoor on self-hosted servers.
Wiz observed multiple threat actors chaining CVE-2026-42018 and CVE-2026-42016 against self-hosted JFrog Artifactory instances between August 15 and September 8, 2026, in some cases obtaining admin access in under five minutes. The critical authentication bypass CVE-2026-82329 was also exploited this month to mint administrator tokens. Attackers installed malicious Groovy plugins, dropped a Rust backdoor with C2 capabilities, uploaded webshells, stole configuration data and cluster join keys, and added SSH keys to new accounts. Wiz estimates 49-62% of internet-reachable Artifactory instances are vulnerable to at least one of the three flaws, and patched releases from 7.111.21 through 7.161.20 are available.
⚡ Weekly Recap: AI-Powered PLC Attacks, GitLab Attacks, Stripe Key Leaks and More
US agencies warn of AI-assisted attacks on exposed Siemens PLCs; the week also saw GitLab CVE-2026-19478 exploited and trojanized npm packages found.
The weekly recap leads with a US government warning that threat actors use AI-generated scripts and Censys/ZoomEye scanning to attack internet-exposed Siemens S7 PLCs in water, energy and manufacturing, calling it an active threat. Other stories include active exploitation of GitLab CVE-2026-19478 (CVSS 9.4, unauthenticated project rewriting), 14 trojanized npm packages delivering the RedC2 4.0 Linux backdoor, and the Zombie Card attack that revives expired Visa cards for contactless payment fraud. It also covers suspected Russian clusters UNC6293, UNC7005 and UNC5976 phishing campaigns, a faster Cloudflare Workers Spectre JWT leak, and a bespoke Cl0p JSP web shell deployed after exploiting PTC Windchill flaws.
Fortinet Patches Critical Vulnerabilities in FortiMonitorOnSight, Chrome Extension
Fortinet patched 10 vulnerabilities including two critical authentication flaws, CVE-2026-84390 (CVSS 9.6) and CVE-2026-84388 (CVSS 9.1), in FortiMonitorOnSight and the FortiPAM Chrome extension.
Fortinet's September patch release fixes CVE-2026-84390, a sensitive-information issue in the FortiMonitorOnSight web portal that lets unauthenticated attackers bypass authentication with forged or reused JWTs. CVE-2026-84388 is an improper authentication flaw in the Fortinet Privileged Access Agent Chrome extension that can allow attackers to proxy a user's browser traffic via a malicious website, requiring upgrades to both FortiPAM 1.9.1/1.8.4 and extension 8.0.1.123+. High-severity information disclosure in FortiSandbox (CVE-2026-26084) and man-in-the-middle risk in the FortiOS/FortiProxy Agentless ZTNA portal (CVE-2026-84393) were also fixed, alongside medium/low issues across FortiManager, FortiAnalyzer, FortiSOAR, FortiClient, FortiSIEM and others. Fortinet did not indicate any of the flaws are being exploited in the wild.
FortiPAM Chrome Extension Vulnerability Lets Malicious Sites Control Browser Proxy and Record Tabs
Fortinet patched CVE-2026-84388 (CVSS 9.1) in its FortiPAM Chrome extension, letting malicious websites alter proxy settings, open tabs and record sessions.
The Fortinet FortiPAM Chrome extension flaw (CVE-2026-84388, CVSS 9.1) lets attacker-controlled domains be trusted as FortiPAM servers because a webRequest listener adds requested hostnames without verifying the initiator. A second issue exposes the extension's message interface to all URLs and accepts non-JWT tokens without validation, enabling unauthenticated session launches, proxy manipulation, tab control and recording; the consent dialog can also be bypassed via shadow-root clicks. Fortinet issued advisory FG-IR-26-168 after a July 17 report and released a fix on August 1, 2026, with no confirmed exploitation in the wild.
AI-Generated Exploit Scripts Target Siemens S7 PLCs in U.S. Critical Infrastructure
NSA, CISA, FBI, DOE and EPA warn that actors use AI-generated Python scripts to exploit internet-exposed Siemens S7 PLCs at U.S. critical infrastructure.
A joint advisory from NSA, CISA, FBI, DOE and EPA describes an active threat in which AI-generated exploit scripts disguised as legitimate monitoring tools target Siemens S7 Series PLCs (S7-200 through S7-1500, including F-series safety controllers). The actors use Censys and ZoomEye scanning to find internet-exposed, outdated PLCs and a custom Python script using snap7 libraries over the S7comm protocol for initial access, credential access and denial of service; no attribution was given. Targeted sectors include Critical Manufacturing, Energy, Water and Wastewater, Chemical, Food and Agriculture, and Commercial Facilities, with potential for process disruption and cascading impacts. A related Dream report details a near-autonomous AI-agent campaign (July 1-4, 2026, 12 waves) against Taiwan government entities, using Hermes and OpenClaw agents with eight parallel sub-agents to crack 85 accounts via password spraying and exfiltrate over 2,564 personnel records, SSO client secrets and database credentials.