Emissary <8.39 XSS via Mustache href injection
CVE-2026-35571 Published on April 7, 2026

Emissary has Stored XSS via Navigation Template Link Injection
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.

NVD

Vulnerability Analysis

CVE-2026-35571 can be exploited with network access, requires user interaction and user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a small impact on confidentiality and integrity, and no impact on availability.

Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
HIGH
User Interaction:
REQUIRED
Scope:
CHANGED
Confidentiality Impact:
LOW
Integrity Impact:
LOW
Availability Impact:
NONE

Weakness Type

What is a XSS Vulnerability?

The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

CVE-2026-35571 has been classified to as a XSS vulnerability or weakness.


Affected Versions

NationalSecurityAgency emissary Version < 8.39.0 is affected by CVE-2026-35571

Exploit Probability

EPSS
0.03%
Percentile
8.07%

EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.