CVE-2026-27639

MEDIUM

Mercator <2026.02.22 - Stored XSS

Title source: llm

Description

Mercator is an open source web application designed to enable mapping of information systems. A stored Cross-Site Scripting (XSS) vulnerability exists in Mercator prior to version 2026.02.22 due to the use of unescaped Blade directives (`{!! !!}`) in display templates. An authenticated user with the User role can inject arbitrary JavaScript payloads into fields such as "contact point" when creating or editing entities. The payload is then executed in the browser of any user who views the affected page, including administrators. Version 2026.02.22 fixes the vulnerability.

Exploits (2)

github WORKING POC 10 stars
by XiaomingX · pythonpoc
https://github.com/XiaomingX/data-cve-poc-py-v1/tree/main/2026/CVE-2026-27639
nomisec WRITEUP
by hadhub · poc
https://github.com/hadhub/CVE-2026-27639-Mercator-XSS

Scores

CVSS v3 5.4
EPSS 0.0004
EPSS Percentile 13.1%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Details

CWE
CWE-79
Status published
Products (1)
sourcentis/mercator < 2026.02.22
Published Feb 25, 2026
Tracked Since Feb 25, 2026