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

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Source ID Title
Github GHSA Github GHSA GHSA-xjhr-fm27-4hmx OpenFUN Richie Observable Timing Discrepancy in its sync_course_run_from_request function
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Fri, 27 Feb 2026 02:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Thu, 26 Feb 2026 20:45:00 +0000

Type Values Removed Values Added
Weaknesses CWE-208
Metrics cvssV3_1

{'score': 4.8, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N'}


Thu, 26 Feb 2026 13:30:00 +0000

Type Values Removed Values Added
First Time appeared Openfun
Openfun richie
Vendors & Products Openfun
Openfun richie

Wed, 25 Feb 2026 17:15:00 +0000

Type Values Removed Values Added
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
References

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published:

Updated: 2026-02-26T19:11:04.934Z

Reserved: 2026-02-16T00:00:00.000Z

Link: CVE-2026-26717

cve-icon Vulnrichment

Updated: 2026-02-26T19:05:51.701Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-02-25T17:25:39.293

Modified: 2026-02-27T14:06:59.787

Link: CVE-2026-26717

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-02-26T13:18:27Z

Weaknesses