CVE-2026-91134
- Source
- https://cve.org/CVERecord?id=CVE-2026-91134
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-91134.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2026-91134
- Aliases
-
- BIT-discourse-2026-91134
- GHSA-54vw-chv3-wjpv
- Published
- 2026-09-24T16:51:34Z
- Modified
- 2026-10-28T02:31:02Z
- Severity
-
- 5.4 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N CVSS Calculator
- Summary
- Discourse: Block post iframes whose encoded userinfo bypasses the allowed_iframes allowlist
- Details
-
Discourse is an open-source discussion platform. Prior to 2026.1.8, 2026.6.3, 2026.7.2, and 2026.8.0, the Discourse post sanitizer allowed a stored cross-origin iframe to bypass the allowed_iframes prefix policy when the iframe src contained encoded userinfo. The sanitizer validated a decoded form differently from the stored iframe src, allowing the browser to interpret an attacker-controlled host while the allowlist check accepted the encoded URL as an allowed prefix. An authenticated user with posting privileges could persist the iframe in a post and cause attacker-controlled cross-origin content to be rendered. This issue is fixed in versions 2026.1.8, 2026.6.3, 2026.7.2, and 2026.8.0.
- Database specific
{ "cna_assigner": "GitHub_M", "cwe_ids": [ "CWE-20" ], "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/91xxx/CVE-2026-91134.json" }- References
-
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/91xxx/CVE-2026-91134.json
- https://github.com/discourse/discourse/security/advisories/GHSA-54vw-chv3-wjpv
- https://nvd.nist.gov/vuln/detail/CVE-2026-91134
- https://github.com/discourse/discourse/commit/0a8015e6c7a5079981843721494d30c9a91f5415
- https://github.com/discourse/discourse/commit/1304b0c04f87534053b0d574ae5a9b9ba13dd590
- https://github.com/discourse/discourse/commit/bac7dd1201911851462483271b4567246fa1309d
- https://github.com/discourse/discourse/commit/fed3a58c48412ce7207b72a4629ddbc44482cd64
- https://github.com/discourse/discourse/pull/42882
Affected packages
Git / github.com/discourse/discourse
Affected ranges
- Type
- GIT
- Repo
- https://github.com/discourse/discourse
- Events
-
Introduced0 Unknown introduced commit / All previous commits are affectedFixedIntroducedFixedIntroducedFixedIntroducedFixedFixedFixedFixedFixed
- Database specific
-
Show details
{ "extracted_events": [ { "range": [ { "introduced": "0" }, { "fixed": "2026.8.0" } ], "source": "AFFECTED_FIELD", "strategy": "StringRangeExpression" }, { "range": [ { "introduced": "2026.7.0-latest" }, { "fixed": "2026.7.2" } ], "source": "AFFECTED_FIELD", "strategy": "StringRangeExpression" }, { "range": [ { "introduced": "2026.6.0-latest" }, { "fixed": "2026.6.3" } ], "source": "AFFECTED_FIELD", "strategy": "StringRangeExpression" }, { "range": [ { "introduced": "2026.1.0-latest" }, { "fixed": "2026.1.8" } ], "source": "AFFECTED_FIELD", "strategy": "StringRangeExpression" }, { "range": [ { "fixed": "0a8015e6c7a5079981843721494d30c9a91f5415" } ], "source": "REFERENCES_COMMIT" }, { "range": [ { "fixed": "1304b0c04f87534053b0d574ae5a9b9ba13dd590" } ], "source": "REFERENCES_COMMIT" }, { "range": [ { "fixed": "bac7dd1201911851462483271b4567246fa1309d" } ], "source": "REFERENCES_COMMIT" }, { "range": [ { "fixed": "fed3a58c48412ce7207b72a4629ddbc44482cd64" } ], "source": "REFERENCES_COMMIT" } ] }