CVE-2026-88871
MEDIUM 5.3 PoC AVAILABLE ALL-YEARSWWBN AVideo through commit c3edcc274c389816d434acadac07ee78eaf330c1 (master, 2026-08-23) contains a cross-site request forgery vulnerability in the CustomizeUser plugin's plugin/CustomizeUser/setSubscribers.json.php endpoint. The script reads users_id and ExtraSubscribers from $_REQUEST and calls User::setExtraSubscribers() without requiring a POST request or a valid CSRF token; autoCSRFGuard() is applied only to POST requests to *.json.php, and the mutation does not pass through ObjectYPT::save()/isUntrustedRequest(), so a cross-origin GET succeeds. An unauthenticated remote attacker who induces a logged-in administrator to load a crafted page (for example an <img> tag pointing at the endpoint) can forge the ExtraSubscribers count displayed on any user's channel. The CustomizeUser plugin is enabled by default, and no patched version was available at the time of reporting.
Public exploit or PoC code exists. The barrier to attack is reduced — watch closely.
Exploitation likelihood
0.2%chance of exploitation in 30 days · 7th percentile
Impact if exploited
5.3CVSS 4.0 · MEDIUM · CNA
- ConfidentialityNone
- IntegrityLow
- AvailabilityNone
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ✓Privileges: No account or privileges required
- ⚠User interaction: Succeeds with passive user activity
- ✓Complexity: No special conditions — reliably repeatable
- ✓Requirements: No special attack requirements
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- reference https://github.com/WWBN/AVideo/security/advisories/GHSA-p9c3-prq7-g8xc
- github-search https://github.com/search?q=%22CVE-2026-88871%22&type=repositories
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-88871/poc.jsonMachine-readable PoC index for this CVE (for automation).For defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-88871/poc.json
Weakness (CWE)
- CWE-352: Cross-Site Request Forgery (CSRF)
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
All CVSS metrics
- MEDIUM 5.3 v4.0 · CNA Primary
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - MEDIUM 4.3 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N - MEDIUM 5.3 v4.0 · NVD Secondary
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/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 - MEDIUM 4.3 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N