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CVE-2026-4923 (GCVE-0-2026-4923)

Vulnerability from cvelistv5 – Published: 2026-03-26 19:02 – Updated: 2026-03-27 13:58
VLAI
Title
path-to-regexp vulnerable to Regular Expression Denial of Service via multiple wildcards
Summary
Impact: When using multiple wildcards, combined with at least one parameter, a regular expression can be generated that is vulnerable to ReDoS. This backtracking vulnerability requires the second wildcard to be somewhere other than the end of the path. Unsafe examples: /*foo-*bar-:baz /*a-:b-*c-:d /x/*a-:b/*c/y Safe examples: /*foo-:bar /*foo-:bar-*baz Patches: Upgrade to version 8.4.0. Workarounds: If you are using multiple wildcard parameters, you can check the regex output with a tool such as https://makenowjust-labs.github.io/recheck/playground/ to confirm whether a path is vulnerable.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-27 13:46 UTC
CWE
  • CWE-1333 - Inefficient Regular Expression Complexity
Assigner
References
Impacted products
Vendor Product Version CPE status
path-to-regexp path-to-regexp Affected: 8.0.0 , < 8.4.0 (semver)
Unaffected: 8.4.0 (semver)
guessed Create a notification for this product.
Credits
blakeembrey UlisesGascon
Show details on NVD website
To clipboard 

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