CVE

CVE-2021-3377

6.1

CVSS

Description

The npm package ansi_up converts ANSI escape codes into HTML. In ansi_up v4, ANSI escape codes can be used to create HTML hyperlinks. Due to insufficient URL sanitization, this feature is affected by a cross-site scripting (XSS) vulnerability. This issue is fixed in v5.0.0.

Attack Vector

Privileges Req.

User Interaction

Updated Oct 24, 2026View on NVD →

S4E scanner

mediumProduct Based Web Vulnerabilities~10 seconds

CVE-2021-3377 Scanner

CVE-2021-3377 scanner - Cross-Site Scripting (XSS) vulnerability in npm package ansi_up

Used 2.9k times · 3.4k assets checked · domain, ipv4, subdomain

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