{"schema":"threatline.record/2","record":{"id":"CVE-2026-91123","aliases":["GHSA-6pwj-wgg8-4rjc"],"summary":"Discourse: Reject literal backslash path separators in iframe src traversal guard","details":"Discourse is an open-source discussion platform. Prior to 2026.1.8, 2026.6.3, 2026.7.2, and 2026.8.0, the iframe src traversal guard did not treat literal backslashes as path separators after decoded dot segments. A crafted source could therefore pass an allowed_iframes subpath check while browser URL normalization moved the iframe outside the intended allowed path. The resulting iframe could load content from a location that the administrator did not allow. This issue is fixed in versions 2026.1.8, 2026.6.3, 2026.7.2, and 2026.8.0.","categories":["Applications & CMS"],"product":"discourse","vendor":"discourse","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-91123","source_modified_at":"2026-09-24T17:11:34.752Z","fetched_at":"2026-10-23T18:52:38.922436Z","product":"discourse","vendor":"discourse","versions":[{"status":"affected","version":"< 2026.8.0"},{"status":"affected","version":">= 2026.7.0-latest, < 2026.7.2"},{"status":"affected","version":">= 2026.6.0-latest, < 2026.6.3"},{"status":"affected","version":">= 2026.1.0-latest, < 2026.1.8"}],"defaultStatus":null},{"source":"GitHub Advisory Database","source_url":"https://github.com/discourse/discourse/security/advisories/GHSA-6pwj-wgg8-4rjc","source_modified_at":"2026-09-14T22:23:57Z","fetched_at":"2026-10-23T22:01:05.715934Z","package":{"ecosystem":"other","name":"Discourse"},"range":">= 0"},{"source":"GitHub Advisory 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Database","source_url":"https://github.com/discourse/discourse/security/advisories/GHSA-6pwj-wgg8-4rjc","source_modified_at":"2026-09-14T22:23:57Z","fetched_at":"2026-10-23T22:01:05.715934Z","package":{"ecosystem":"other","name":"Discourse"},"version":"2026.8.0"},{"source":"GitHub Advisory Database","source_url":"https://github.com/discourse/discourse/security/advisories/GHSA-6pwj-wgg8-4rjc","source_modified_at":"2026-09-14T22:23:57Z","fetched_at":"2026-10-23T22:01:05.715934Z","package":{"ecosystem":"other","name":"Discourse"},"version":"2026.7.2"},{"source":"GitHub Advisory Database","source_url":"https://github.com/discourse/discourse/security/advisories/GHSA-6pwj-wgg8-4rjc","source_modified_at":"2026-09-14T22:23:57Z","fetched_at":"2026-10-23T22:01:05.715934Z","package":{"ecosystem":"other","name":"Discourse"},"version":"2026.6.3"},{"source":"GitHub Advisory 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Database","url":"https://github.com/discourse/discourse/security/advisories/GHSA-6pwj-wgg8-4rjc","fetched_at":"2026-10-23T22:01:05.715934Z","source_modified_at":"2026-09-14T22:23:57Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-91123","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","GitHub Advisory Database","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/discourse/discourse/security/advisories/GHSA-6pwj-wgg8-4rjc","tags":["x_refsource_CONFIRM"]},{"source":"CVE List","url":"https://github.com/discourse/discourse/pull/42882","tags":["x_refsource_MISC"]},{"source":"CVE List","url":"https://github.com/discourse/discourse/commit/042d7b159beda4f74d23e245e8b2e396d9ff8318","tags":["x_refsource_MISC"]},{"source":"CVE List","url":"https://github.com/discourse/discourse/commit/097ce5600a2d74d9c68e57974597ab2684bd2a24","tags":["x_refsource_MISC"]},{"source":"CVE List","url":"https://github.com/discourse/discourse/commit/0b5a27e689925edce9ba9b14110022435d2b94be","tags":["x_refsource_MISC"]},{"source":"CVE List","url":"https://github.com/discourse/discourse/commit/142f5155ad8e56ddb8012c4e70c69a03dedc0579","tags":["x_refsource_MISC"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"none","automatable":"yes","technical_impact":"partial","assessed_at":"2026-09-24T17:11:25.606443Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-09-24T17:11:34.752Z","content_hash":"2dff5d74ef651e713429016ea6f1ff50222350c467ad1ef95c33ce877466de8e"}}