CVE-2026-63466

Published: Ago 21, 2026 Last Modified: Ago 21, 2026
ExploitDB:
Other exploit source:
Google Dorks:
MEDIUM 4,1
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: low
User Interaction: required
Scope: changed
Confidentiality: none
Integrity: low
Availability: none

Description

AI Translation Available

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.

116

Improper Encoding or Escaping of Output

Draft
Abstraction: Class Structure: Simple
Common Consequences
Security Scopes Affected:
Integrity Confidentiality Availability Access Control
Potential Impacts:
Modify Application Data Execute Unauthorized Code Or Commands Bypass Protection Mechanism
Applicable Platforms
Technologies: Not Technology-Specific, AI/ML, Database Server, Web Server
Likelihood of Exploit: High
View CWE Details
https://github.com/Unleash/unleash/commit/002012cfdbedd2e9b…
https://github.com/Unleash/unleash/commit/002012cfdbedd2e9b7db9dc83b9f549f761db…
https://github.com/Unleash/unleash/releases/tag/v8.0.3
https://github.com/Unleash/unleash/releases/tag/v8.0.3
https://github.com/Unleash/unleash/security/advisories/GHSA…
https://github.com/Unleash/unleash/security/advisories/GHSA-w4mq-xh27-6xpx