Vulnerability Description
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
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/Rickidevs/CVE-2026-26717
- https://github.com/openfun/richie/commit/a1b5bbda3403d7debb466c303a32852925fcba5
- https://medium.com/@ordogh/cve-2026-26717-hmac-timing-attack-in-openfun-richie-l
FAQ
What is CVE-2026-26717?
CVE-2026-26717 is a vulnerability with a CVSS score of 4.8 (MEDIUM). 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....
How severe is CVE-2026-26717?
CVE-2026-26717 has been rated MEDIUM with a CVSS base score of 4.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-26717?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.