{"id":"CVE-2026-53961","summary":"Discourse: Forged AWS SNS bounce notifications can disable a targeted user's email (missing TopicArn binding)","details":"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.","aliases":["BIT-discourse-2026-53961","GHSA-8f9m-v436-wr3x"],"modified":"2026-10-28T02:30:42.464869544Z","published":"2026-07-09T21:48:11.449Z","database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-345"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53961.json"},"references":[{"type":"WEB","url":"https://github.com/discourse/discourse/releases/tag/v2026.1.5"},{"type":"WEB","url":"https://github.com/discourse/discourse/releases/tag/v2026.4.2"},{"type":"WEB","url":"https://github.com/discourse/discourse/releases/tag/v2026.5.1"},{"type":"WEB","url":"https://github.com/discourse/discourse/releases/tag/v2026.6.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53961.json"},{"type":"ADVISORY","url":"https://github.com/discourse/discourse/security/advisories/GHSA-8f9m-v436-wr3x"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53961"},{"type":"FIX","url":"https://github.com/discourse/discourse/commit/3a3d315a85ef3c6aabfc7e7bb38702059784f06b"},{"type":"FIX","url":"https://github.com/discourse/discourse/commit/61f12e13aa1b760f81d5ff60f12e3a7e77434b94"},{"type":"FIX","url":"https://github.com/discourse/discourse/commit/958f0cd831d65a49ec75f05343ca2c167679f0ea"},{"type":"FIX","url":"https://github.com/discourse/discourse/commit/aea35190791261bab258ebab05da279e78cdd0e6"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/discourse/discourse","events":[{"introduced":"322d3c0ac6a8f133b3f82875e9dbbe310f638c1b"},{"fixed":"c06899647d758493d95a5b301e573ffa3db1e878"},{"introduced":"fdd750d960e603415db62242eca3c30d68e366db"},{"fixed":"4bbdddfc6700ca23604242111d4fa0e00347af97"},{"introduced":"640840d818f4ee9375829ece0ef452923bb0c012"},{"fixed":"598586ccf2e046a25d4b54132e4e1feb47f24e98"},{"introduced":"06d03da34c4ed09ea59f917f045ba250d2b6320d"},{"fixed":"3a3d315a85ef3c6aabfc7e7bb38702059784f06b"},{"fixed":"61f12e13aa1b760f81d5ff60f12e3a7e77434b94"},{"fixed":"958f0cd831d65a49ec75f05343ca2c167679f0ea"},{"fixed":"aea35190791261bab258ebab05da279e78cdd0e6"},{"fixed":"06d03da34c4ed09ea59f917f045ba250d2b6320d"}],"database_specific":{"extracted_events":[{"range":[{"introduced":"2026.1.0"},{"fixed":"2026.1.5"}],"source":"CPE_RANGE","cpe":"cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*"},{"range":[{"introduced":"2026.4.0"},{"fixed":"2026.4.2"}],"source":"CPE_RANGE","cpe":"cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*"},{"source":"CPE_RANGE","cpe":"cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*","range":[{"introduced":"2026.5.0"},{"fixed":"2026.5.1"}]},{"range":[{"introduced":"2026.6.0"},{"last_affected":"2026.6.0"}],"source":"CPE_STRING","cpe":"cpe:2.3:a:discourse:discourse:2026.6.0:*:*:*:latest:*:*:*"},{"source":"REFERENCES_COMMIT","range":[{"fixed":"3a3d315a85ef3c6aabfc7e7bb38702059784f06b"}]},{"range":[{"fixed":"61f12e13aa1b760f81d5ff60f12e3a7e77434b94"}],"source":"REFERENCES_COMMIT"},{"range":[{"fixed":"958f0cd831d65a49ec75f05343ca2c167679f0ea"}],"source":"REFERENCES_COMMIT"},{"range":[{"fixed":"aea35190791261bab258ebab05da279e78cdd0e6"}],"source":"REFERENCES_COMMIT"},{"original_tag":"v2026.1.5","range":[{"fixed":"c06899647d758493d95a5b301e573ffa3db1e878"}],"source":"REFERENCES_TAG"},{"original_tag":"v2026.4.2","range":[{"fixed":"4bbdddfc6700ca23604242111d4fa0e00347af97"}],"source":"REFERENCES_TAG"},{"range":[{"fixed":"598586ccf2e046a25d4b54132e4e1feb47f24e98"}],"source":"REFERENCES_TAG","original_tag":"v2026.5.1"},{"source":"REFERENCES_TAG","original_tag":"v2026.6.0","range":[{"fixed":"06d03da34c4ed09ea59f917f045ba250d2b6320d"}]}]}}],"versions":["2026.6.0","v2026.5.0","v2026.1.4","v2026.4.1","v2026.5.0-latest.1","v2026.4.0","v2026.5.0-latest","v2026.1.3","v2026.4.0-latest","v2026.1.2","v2026.1.1","v2026.1.0","stable","esr","v2026.1.0-latest"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53961.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L"}]}