CVE-2026-4923
Received
Received - Intake
Regular Expression ReDoS in Wildcard Path Parameters (v
Publication date: 2026-03-26
Last updated on: 2026-04-16
Assigner: openjs
Description
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.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| pillarjs | path-to-regexp | From 8.0.0 (inc) to 8.4.0 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-1333 | The product uses a regular expression with an inefficient, possibly exponential worst-case computational complexity that consumes excessive CPU cycles. |