CVE-2026-53636
Open edX LTI OAuth Replay Attack
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
Open edX Platform enables the authoring and delivery of online learning at any scale. Prior to commit 3a5ac85, a security vulnerability has been identified in the Open edX LMS platform's LTI (Learning Tools Interoperability) Provider implementation. The validate_timestamp_and_nonce function in lms/djangoapps/lti_provider/signature_validator.py does not validate OAuth nonces or timestamps, allowing an attacker who captures a valid LTI launch request to replay it an unlimited number of times without detection. This issue has been patched via commit 3a5ac85.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium4.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N |
| NVDNVD · Deferred | 3.1 | Medium4.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.28% · top 79% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.7.
Weakness
Affected products
- affected < 3a5ac856c79557c5c74d8b3e6578f289d7cceecd
References (4)
- https://github.com/openedx/openedx-platform/security/advisories/GHSA-6gm5-c49g-p3h9 (opens in a new tab)x_refsource_CONFIRMexploit
- https://github.com/openedx/openedx-platform/commit/0a92cf25de8844bf840ffd5d18dcfd940031a2ba (opens in a new tab)x_refsource_MISC
- https://github.com/openedx/openedx-platform/commit/3a5ac856c79557c5c74d8b3e6578f289d7cceecd (opens in a new tab)x_refsource_MISC
- https://github.com/openedx/openedx-platform/commit/50af17b05d82a8c7e8e690cc2783a8a0ba330bc3 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-53636)Record last updated .