CVE-2026-85272 Open edX Platform: Path traversal via prefix-bypass in safe_extractall Path Validation
A path traversal vulnerability in Open edX allows course authors to corrupt files in sibling course directories via crafted archives.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-85272?
CVE-2026-85272 is a medium-severity path traversal vulnerability in openedx-platform, published on 18 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Open edX Platform enables the authoring and delivery of online learning at any scale. From Aspen.1 until Ulmo and Verawood.1, openedx/core/lib/extract_archive.py uses _is_bad_path to validate safe_extractall targets by comparing resolved path strings with startswith instead of comparing path components. A course author or staff user with course import permission can submit a crafted .tar.gz archive through the import_olx flow initiated by cms.djangoapps.contentstore.views.import_export.import_handler. An archive member can therefore escape into a sibling course staging directory whose name shares the attacker's base64 directory prefix, causing limited cross-tenant file corruption. Zip archives are not practically affected because ZipFile.extractall strips parent traversal segments, and the advisory does not establish arbitrary filesystem writes, file reads, or direct code execution. This issue is fixed in Ulmo and Verawood.1.
Weakness: CWE-22
Which versions are affected by CVE-2026-85272?
How do I fix CVE-2026-85272?
No fix has been published for CVE-2026-85272 yet. Limit exposure of the affected software until one is available.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-85272 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-85272 exists.
Sources
Also known as GHSA-6cmm-8875-5pcw.