{"id":"CVE-2026-63466","revision":"41227d82663a4f93adda00cdba6c161f","records":[{"revision":"41227d82663a4f93adda00cdba6c161f","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-63466","aliases":[],"title":"Unleash: Global Mustache.escape override disables HTML escaping process-wide, enabling Slack/Teams link-injection via unrestricted username","description":"Unleash is an open-source feature management platform. Prior to 8.0.3, FeatureEventFormatterMd.format in src/lib/addons/feature-event-formatter-md.ts assigns Mustache.escape to an identity function before rendering action and path templates. Because Mustache.escape is process-wide, the assignment disables escaping for subsequent Mustache.render calls in email-service.ts, webhook.ts, datadog.ts, and new-relic.ts. An editor-level user can place Slack or Microsoft Teams link syntax in an unrestricted username, trigger a feature event, and inject an attacker-labeled link into a trusted outbound notification channel, while other Mustache sinks remain unescaped until restart. This issue is fixed in version 8.0.3.","state":0,"publishedAt":"2026-08-21T18:21:46.526+00:00","modifiedAt":"2026-08-21T21:43:35.526+00:00","affected":[{"ecosystem":"Vendor product","name":"unleash","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Unleash\",\n                    \"product\": \"unleash\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 8.0.3\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:L/A:N","score":4.1,"severity":"MEDIUM"}],"references":["https://github.com/Unleash/unleash/security/advisories/GHSA-w4mq-xh27-6xpx","https://github.com/Unleash/unleash/commit/002012cfdbedd2e9b7db9dc83b9f549f761db22e","https://github.com/Unleash/unleash/releases/tag/v8.0.3"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-63466","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-63466","identifiers":["CVE-2026-63466"]},"retained":false,"historicalAffected":[]}],"coverage":[]}