Low

Regular Expression Denial of Service in debug

  • Disclosed: 09.08.2018
  • Updated: 11.10.2026 10:22

Affected versions of debug are vulnerable to regular expression denial of service when untrusted user input is passed into the o formatter.

As it takes 50,000 characters to block the event loop for 2 seconds, this issue is a low severity issue.

This was later re-introduced in version v3.2.0, and then repatched in versions 3.2.7 and 4.3.1.

Recommendation

Version 2.x.x: Update to version 2.6.9 or later. Version 3.1.x: Update to version 3.1.0 or later. Version 3.2.x: Update to version 3.2.7 or later. Version 4.x.x: Update to version 4.3.1 or later.

Affected software

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PlatformPackageVulnerable versionsFixed in
npm package debug < 2.6.9, >= 3.0.0, < 3.1.0, >= 3.2.0, < 3.2.7, >= 4.0.0, < 4.3.1 2.6.9, 3.1.0, 3.2.7, 4.3.1

References

CVSS score 3.7/10
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
Weakness (CWE)
CWE-400
Platform
npm
Package
debug
Disclosed
09.08.2018
Updated
11.10.2026 10:22

Sources and licenses

OSV / GitHub Advisory Database - GHSA-gxpj-cx7g-858c - CC BY 4.0

Vulnerability history: debug

All published vulnerabilities of this package (npm package), newest first. Shows whether this is a one-off slip or a package that needs watching.

Total entries
3
First → latest
08.2018 09.2025
Without a fix
0
Exploited in attacks
0

Severity breakdown

  • High 2
  • Low 1

Disclosures per year

  1. 2018: 1
  2. 2019: 0
  3. 2020: 0
  4. 2021: 0
  5. 2022: 0
  6. 2023: 1
  7. 2024: 0
  8. 2025: 1
  9. 2026: 0
  1. High CVE-2025-59144 >= 4.4.2, < 4.4.3 4.4.3
  2. High · 7.5 CVE-2017-20165 >= 3.0.0, < 3.1.0, < 2.6.9 3.1.0, 2.6.9
  3. Regular Expression Denial of Service in debug this entry
    Low · 3.7 CVE-2017-16137 < 2.6.9, >= 3.0.0, < 3.1.0, >= 3.2.0, < 3.2.7, >= 4.0.0, < 4.3.1 2.6.9, 3.1.0, 3.2.7, 4.3.1

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