CVE-2026-40911
WWBN AVideo YPTSocket WebSocket Broadcast Relay Leads to Unauthenticated Cross-User JavaScript Execution via Client-Side eval() Sinks
- State
- Published
- Severity
- 10.0 Critical
- Published
- Apr 21, 2026
- Updated
- Apr 22, 2026
- Reserved
- Apr 15, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 10.0 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H | GitHub_M |
Weaknesses
- CWE-94 Improper Control of Generation of Code ('Code Injection')
Affected Products
| Product | Versions |
|---|---|
AVideoWWBN |
|
References
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