MEDIUM4.8
PYSEC-2026-3052
OpenFUN Richie Observable Timing Discrepancy in its sync_course_run_from_request function
Quick fix
PYSEC-2026-3052 — richie: upgrade to the fixed version with the command below.
pip install --upgrade 'richie>=3.3.0'Details
An issue in OpenFUN Richie (LMS) in src/richie/apps/courses/api.py. The application used the non-constant time == operator for HMAC signature verification in the sync_course_run_from_request function. This allows remote attackers to forge valid signatures and bypass authentication by measuring response time discrepancies.
Are you affected?
Enter the version of the package you're using.
Affected packages
References
- https://nvd.nist.gov/vuln/detail/CVE-2026-26717[ADVISORY]
- https://github.com/openfun/richie/commit/a1b5bbda3403d7debb466c303a32852925fcba5f[WEB]
- https://github.com/Rickidevs/CVE-2026-26717[WEB]
- https://github.com/openfun/richie[PACKAGE]
- https://medium.com/@ordogh/cve-2026-26717-hmac-timing-attack-in-openfun-richie-lms-f04377efe83d?postPublishedType=repub[WEB]
- https://pypi.org/project/richie[PACKAGE]
- https://github.com/advisories/GHSA-xjhr-fm27-4hmx[ADVISORY]