npm-check-updates vulnerability

npm-check-updates through 23.0.2, fixed in commit b554b84, contains a terminal escape sequence injection vulnerability that allows an attacker to embed arbitrary terminal control characters in a dependency's package.json homepage or repository URL fields. When a developer runs ncu with the --format homepage or --format repo option, unfiltered escape sequences are written directly to the terminal, enabling malicious output manipulation or other terminal-dependent effects.

Published 10 Aug 2026Updated 24 Sep 20264 sources
CVSS 5.3

What happened

npm-check-updates through 23.0.2, fixed in commit b554b84, contains a terminal escape sequence injection vulnerability that allows an attacker to embed arbitrary terminal control characters in a dependency's package.json homepage or repository URL fields. When a developer runs ncu with the --format homepage or --format repo option, unfiltered escape sequences are written directly to the terminal, enabling malicious output manipulation or other terminal-dependent effects.

Affected versions

npm-check-updates: 0 through 23.0.2 (semver) Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

  • Apply vendor-provided updates or mitigations.
  • Review affected product exposure and access logs.

Public PoC references

No public PoC reference has passed the current publication threshold.