{"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": "2026-08-21T18:21:46.526Z"}, "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"}}}}

{}

{"affected": [{"affectedData": [{"product": "unleash", "vendor": "Unleash", "versions": [{"status": "affected", "version": "< 8.0.3"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "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."}], "id": "CVE-2026-63466", "lastModified": "2026-08-21T19:17:32.117", "metrics": {"cvssMetricV31": [{"cvssData": {"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"}, "exploitabilityScore": 2.3, "impactScore": 1.4, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-08-21T19:17:32.117", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/Unleash/unleash/commit/002012cfdbedd2e9b7db9dc83b9f549f761db22e"}, {"source": "security-advisories@github.com", "url": "https://github.com/Unleash/unleash/releases/tag/v8.0.3"}, {"source": "security-advisories@github.com", "url": "https://github.com/Unleash/unleash/security/advisories/GHSA-w4mq-xh27-6xpx"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-116"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{"created": "2026-08-21T20:00:13.885712+00:00", "updated": "2026-08-21T20:00:13.885721+00:00", "vendors": []}