CVE-2026-89256

9.3 CRITICAL 0.4% exploit odds Fix listed XSS Web app

What it is

AVideo through commit c3edcc274c389816d434acadac07ee78eaf330c1 contains a stored cross-site scripting vulnerability in the Bookmark plugin where chapter names are not encoded before being concatenated into public watch-page HTML. A video owner can inject malicious scripts via the bookmark name parameter, and every visitor of that video executes the payload in the AVideo origin.

At a glance

Exploitability: Can be exploited over the network with a low-privilege account, but needs a user to act. High risk of data exposure, data tampering.
Exploit odds: 0.4% chance of exploitation in the next 30 days (EPSS).
Fix: A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

2026-09-11 12:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2026-09-11 20:19 UTC Last updatedMost recent change to the record

Details

Published: 2026-09-11 12:16 UTC
Last modified: 2026-09-11 20:19 UTC
Exploit probability: 0.4% · EPSS, next 30 days
Weakness: CWE-79 · Cross-site scripting
Record status: Deferred

Attack profile CVSS 4.0 · 9.3

Attack vector: Network
Complexity: Low
Attack requirements: None
Privileges needed: Low
User interaction: Passive
Confidentiality: High
Integrity: High
Availability: None

Raw vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

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Fix and advisories

References

NVD record · CVE.org record