RCE in Wwbn Avideo
CVE-2026-40911
WWBN AVideo is an open source video platform. In versions 29.0 and prior, the YPTSocket plugin's WebSocket server relays attacker-supplied JSON message bodies to every connected client without sanitizing the `msg` or `callback` fields. On the client side, `plugin/YPTSocket/script.js` contains two `eval()` sinks fed directly by those relayed fields (`json.msg.autoEvalCodeOnHTML` at line 568 and `json.callback` at line 95). Because tokens are minted for anonymous visitors and never revalidated beyond decryption, an unauthenticated attacker can broadcast arbitrary JavaScript that executes in the origin of every currently-connected user (including administrators), resulting in universal account takeover, session theft, and privileged action execution. Commit c08694bf6264eb4decceb78c711baee2609b4efd contains a fix.
Vulnerability class: RCE (Remote Code Execution)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 10.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.009 (57.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 58th percentile — 57.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.009 · change: +0.002
Affected products
- Wwbn Avideo — versions <= 29.0
Weakness classification (CWE)
References
- github.com/WWBN/AVideo/security/advisories/GHSA-gph2-j4c9-vhhr (Exploit, Vendor Advisory)
- github.com/WWBN/AVideo/commit/c08694bf6264eb4decceb78c711baee2609b4efd (Patch)
Frequently asked questions
- What is CVE-2026-40911?
- CVE-2026-40911 is a critical-severity vulnerability in Wwbn Avideo, classified under Code Injection. CVSS score: 10.0/10. Published 2026-04-21.
- How severe is CVE-2026-40911?
- Critical severity. CVSS v3 base score is 10.0 out of 10.