Trusted notification link injection via global escape override
Published Aug 21, 2026 · Updated Aug 21, 2026
Output neutralization failure in Unleash before 8.0.3 allows remote authenticated users to inject labeled links into chat notifications. FeatureEventFormatterMd.format replaces the process-wide Mustache.escape function with an identity function, so later email, webhook, Datadog, and New Relic template renders leave attacker-controlled values unescaped. Editor-level access and a triggered feature event are required; the resulting attacker-labeled Slack or Teams link appears inside a trusted outbound notification.
Summary
What happened
Output neutralization failure in Unleash before 8.0.3 allows remote authenticated users to inject labeled links into chat notifications. FeatureEventFormatterMd.format replaces the process-wide Mustache.escape function with an identity function, so later email, webhook, Datadog, and New Relic template renders leave attacker-controlled values unescaped. Editor-level access and a triggered feature event are required; the resulting attacker-labeled Slack or Teams link appears inside a trusted outbound notification.
The record
- CVE
- CVE-2026-63466
- Published
- Aug 21, 2026
- Updated
- Aug 21, 2026
- Vendor
- Unleash
- Product
- Unleash
- Classifications
- CWE-116, T1566.002
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 21, 2026CVE publishedPublication date reported by the CVE source.
- Aug 21, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 8.0.3
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- GHSA-w4mq-xh27-6xpx reproduction procedureproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo