CVE-2025-42620

HIGH

CIRCL Vulnerability-Lookup < 2.18.0 - Stored Cross-Site Scripting via Bundle and Comment Markdown Rendering

Title source: llm
STIX 2.1

Description

In affected versions, vulnerability-lookup handled user-controlled content in comments and bundles in an unsafe way, which could lead to stored Cross-Site Scripting (XSS). On the backend, the related_vulnerabilities field of bundles accepted arbitrary strings without format validation or proper sanitization. On the frontend, comment and bundle descriptions were converted from Markdown to HTML and then injected directly into the DOM using string templates and innerHTML. This combination allowed an attacker who could create or edit comments or bundles to store crafted HTML/JavaScript payloads which would later be rendered and executed in the browser of any user visiting the affected profile page (user.html).  This issue affects Vulnerability-Lookup: before 2.18.0.

References (1)

Core 1
Core References

Scores

CVSS v4 8.3
EPSS 0.0025
EPSS Percentile 15.8%
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:H/VI:N/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-79
Status published
Products (1)
CIRCL/Vulnerability-Lookup < 2.18.0
Published Dec 08, 2025
Tracked Since Feb 18, 2026