{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-63466","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-07-16T21:37:45.768Z","datePublished":"2026-08-21T18:21:46.526Z","dateUpdated":"2026-08-21T21:43:35.526Z"},"containers":{"cna":{"title":"Unleash: Global Mustache.escape override disables HTML escaping process-wide, enabling Slack/Teams link-injection via unrestricted username","problemTypes":[{"descriptions":[{"cweId":"CWE-116","lang":"en","description":"CWE-116: Improper Encoding or Escaping of Output","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":4.1,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"LOW","privilegesRequired":"LOW","scope":"CHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:L/A:N","version":"3.1"}}],"references":[{"name":"https://github.com/Unleash/unleash/security/advisories/GHSA-w4mq-xh27-6xpx","tags":["x_refsource_CONFIRM"],"url":"https://github.com/Unleash/unleash/security/advisories/GHSA-w4mq-xh27-6xpx"},{"name":"https://github.com/Unleash/unleash/commit/002012cfdbedd2e9b7db9dc83b9f549f761db22e","tags":["x_refsource_MISC"],"url":"https://github.com/Unleash/unleash/commit/002012cfdbedd2e9b7db9dc83b9f549f761db22e"},{"name":"https://github.com/Unleash/unleash/releases/tag/v8.0.3","tags":["x_refsource_MISC"],"url":"https://github.com/Unleash/unleash/releases/tag/v8.0.3"}],"affected":[{"vendor":"Unleash","product":"unleash","versions":[{"version":"< 8.0.3","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-08-21T18:21:46.526Z"},"descriptions":[{"lang":"en","value":"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."}],"source":{"advisory":"GHSA-w4mq-xh27-6xpx","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-21T20:58:22.218056Z","id":"CVE-2026-63466","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-08-21T21:43:35.526Z"}}]}}