Vulnerability Description
Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, the AWS SES bounce webhook at POST /webhooks/aws verified that SNS messages were signed by Amazon but did not bind them to trusted TopicArn values, allowing any AWS account holder to publish validly signed forged Bounce notifications that revoke a targeted user email. This issue is fixed in versions 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Discourse | Discourse | >= 2026.1.0, < 2026.1.5 |
Related Weaknesses (CWE)
References
- https://github.com/discourse/discourse/commit/3a3d315a85ef3c6aabfc7e7bb387020597Patch
- https://github.com/discourse/discourse/commit/61f12e13aa1b760f81d5ff60f12e3a7e77Patch
- https://github.com/discourse/discourse/commit/958f0cd831d65a49ec75f05343ca2c1676Patch
- https://github.com/discourse/discourse/commit/aea35190791261bab258ebab05da279e78Patch
- https://github.com/discourse/discourse/releases/tag/v2026.1.5Release Notes
- https://github.com/discourse/discourse/releases/tag/v2026.4.2Release Notes
- https://github.com/discourse/discourse/releases/tag/v2026.5.1Release Notes
- https://github.com/discourse/discourse/releases/tag/v2026.6.0Release Notes
- https://github.com/discourse/discourse/security/advisories/GHSA-8f9m-v436-wr3xVendor Advisory
FAQ
What is CVE-2026-53961?
CVE-2026-53961 is a vulnerability with a CVSS score of 6.5 (MEDIUM). Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, the AWS SES bounce webhook at POST /webhooks/aws verified that SNS messages were signed by Amazon ...
How severe is CVE-2026-53961?
CVE-2026-53961 has been rated MEDIUM with a CVSS base score of 6.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-53961?
Check the references section above for vendor advisories and patch information. Affected products include: Discourse Discourse.