CVE-2026-43877
MEDIUMWWBN AVideo is an open source video platform. In versions up to and including 29.0, objects/userSavePhoto.php is a legacy profile-photo endpoint that accepts a base64 POST parameter…
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 up to and including 29.0, objects/userSavePhoto.php is a legacy profile-photo endpoint that accepts a base64 POST parameter and writes the decoded bytes to videos/userPhoto/photo<users_id>.png. Its only access control is User::isLogged(). It does not end in .json.php, so it is excluded from the project's global autoCSRFGuard (which is suffix-scoped in objects/include_config.php). There is no CSRF token, no Origin/Referer check, and no MIME validation of the decoded bytes. Because AVideo's default cookie policy is SameSite=None; Secure on HTTPS (objects/functionsPHP.php:227), an attacker who lures a logged-in user to a malicious page can overwrite that user's profile photo with arbitrary bytes and also triggers a site-wide clearCache(true) on every forged request. Commit 9c38468041505e637101c5943c5370c68f48e3ac contains an updated fix.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for CVE-2026-43877 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-43877 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-43877. 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-2026-43877 in your dependencies?
O3 detects CVE-2026-43877 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.