Description
Emissary is a P2P based data-driven workflow engine. Prior to 8.39.0, Mustache navigation templates interpolated configuration-controlled link values directly into href attributes without URL scheme validation. An administrator who could modify the navItems configuration could inject javascript: URIs, enabling stored cross-site scripting (XSS) against other authenticated users viewing the Emissary web interface. This vulnerability is fixed in 8.39.0.
Affected products
nsa: emissary
References2
- github.com/NationalSecurityAgency/emissary/pull/1293 Patch
- github.com/NationalSecurityAgency/emissary/security/advisories/… ExploitMitigationThird Party Advisory
Metrics
- CVSS 3.1
-
4.8
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 8 · as of 12 November 2026
- CWE
- CWE-79
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.