Path Traversal in Wwbn Avideo
CVE-2026-40909
WWBN AVideo is an open source video platform. In versions 29.0 and prior, the locale save endpoint (`locale/save.php`) constructs a file path by directly concatenating `$_POST['flag']` into the path at line 30 without any sanitization. The `$_POST['code']` parameter is then written verbatim to that path via `fwrite()` at line 40. An admin attacker (or any user who can CSRF an admin, since no CSRF token is checked and cookies use `SameSite=None`) can traverse out of the `locale/` directory and write arbitrary `.php` files to any writable location on the filesystem, achieving Remote Code Execution. Commit 57f89ffbc27d37c9d9dd727212334846e78ac21a fixes the issue.
Vulnerability class: Path Traversal (Directory Traversal)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.7 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.008 (55.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 56th percentile — 55.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.007 · newest: 0.008 · change: +0.002
Affected products
- Wwbn Avideo — versions <= 29.0
Weakness classification (CWE)
References
- github.com/WWBN/AVideo/security/advisories/GHSA-6rc6-p838-686f (Exploit, Vendor Advisory)
- github.com/WWBN/AVideo/commit/57f89ffbc27d37c9d9dd727212334846e78ac21a (Patch)
Frequently asked questions
- What is CVE-2026-40909?
- CVE-2026-40909 is a high-severity vulnerability in Wwbn Avideo, classified under Path Traversal. CVSS score: 8.7/10. Published 2026-04-21.
- How severe is CVE-2026-40909?
- High severity. CVSS v3 base score is 8.7 out of 10.