Vulnerability library
Security checkNovember 04, 2025

ansi_up cross-site scripting vulnerability

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Medium severitynpmansi_up

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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.

Recommendation

Update the ansi_up package to the latest compatible version. Followings are version details:

  • Affected version(s): < 5.0.0
  • Patched version(s): 5.0.0

References

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