CVE-2026-91123

{"id": "CVE-2026-91123", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-91123", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-09-24T17:11:25.606443Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "CHANGED", "version": "3.1", "baseScore": 7.2, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 2.7, "exploitabilityScore": 3.9}]}, "affected": [{"source": "security-advisories@github.com", "affectedData": [{"vendor": "discourse", "product": "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"}]}]}], "published": "2026-09-24T17:17:08.560", "references": [{"url": "https://github.com/discourse/discourse/commit/042d7b159beda4f74d23e245e8b2e396d9ff8318", "source": "security-advisories@github.com"}, {"url": "https://github.com/discourse/discourse/commit/097ce5600a2d74d9c68e57974597ab2684bd2a24", "source": "security-advisories@github.com"}, {"url": "https://github.com/discourse/discourse/commit/0b5a27e689925edce9ba9b14110022435d2b94be", "source": "security-advisories@github.com"}, {"url": "https://github.com/discourse/discourse/commit/142f5155ad8e56ddb8012c4e70c69a03dedc0579", "source": "security-advisories@github.com"}, {"url": "https://github.com/discourse/discourse/pull/42882", "source": "security-advisories@github.com"}, {"url": "https://github.com/discourse/discourse/security/advisories/GHSA-6pwj-wgg8-4rjc", "source": "security-advisories@github.com"}], "vulnStatus": "Deferred", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-22"}]}], "descriptions": [{"lang": "en", "value": "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."}], "lastModified": "2026-09-24T18:19:06.883", "sourceIdentifier": "security-advisories@github.com"}