CVE-2026-4923

path-to-regexp vulnerable to Regular Expression Denial of Service via multiple wildcards

MEDIUM
5.9
CVSS Score
Published: March 26, 2026 at 07:02 PM UTC
Updated: June 17, 2026 at 10:57 AM UTC
2 products affected across 2 vendorsPath To RegexpPath To Regexp

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Severity
MEDIUM5.9
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

8.0.0 ≤ v < 8.4.0
8.0.0 ≤ v < 8.4.08.0.0
Vendor states this is fixed in 8.4.0 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (1)

Third Party Advisory
Source: cverecord
https://cna.openjsf.org/security-advisories.html

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.9MEDIUMopenjs
Vector?

Quick Info

StatusANALYZED
CWE
CWE-1333

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