CVE-2026-40935
MEDIUMWWBN AVideo is an open source video platform. In versions 29.0 and prior, `objects/getCaptcha.php` accepts the CAPTCHA length (`ql`) directly from the query string with no clamping…
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Description
WWBN AVideo is an open source video platform. In versions 29.0 and prior, objects/getCaptcha.php accepts the CAPTCHA length (ql) directly from the query string with no clamping or sanitization, letting any unauthenticated client force the server to generate a 1-character CAPTCHA word. Combined with a case-insensitive strcasecmp comparison over a ~33-character alphabet and the fact that failed validations do NOT consume the stored session token, an attacker can trivially brute-force the CAPTCHA on any endpoint that relies on Captcha::validation() (user registration, password recovery, contact form, etc.) in at most ~33 requests per session. Commit bf1c76989e6a9054be4f0eb009d68f0f2464b453 contains a fix.
Affected Products
avideowwbnDetection & mitigation playbook
Vendor / applianceDetect
Inventory every wwbn avideo deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for exploitation at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.
Remediation status
No patch has shipped for CVE-2026-40935 yet — track the wwbn avideo advisory for a fixed release and apply the workarounds below in the meantime.
Mitigate without a patch
Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.
How O3 protects you
O3 detects and blocks CVE-2026-40935 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.
Tailored to CVE-2026-40935. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-40935 being exploited in your environment?
O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2026-40935 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.