path-to-regexp vulnerable to Regular Expression Denial of Service via multiple wildcards
cve-program · CVE-2026-4923
PublishedImpact: 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.
Read the publisher's advisoryeuvd · EUVD-2026-16322
PublishedImpact: 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.
Read the publisher's advisorynvd · CVE-2026-4923
PublishedImpact: 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.
Read the publisher's advisoryosv · GHSA-27v5-c462-wpq7
Published### 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 developers are using multiple wildcard parameters, they can check the regex output with a tool such as https://makenowjust-labs.github.io/recheck/playground/ to confirm whether a path is vulnerable.
Read the publisher's advisoryAffected versions, risk and source history
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path-to-regexp vulnerable to Regular Expression Denial of Service via multiple wildcards
osv · GHSA-27v5-c462-wpq7 · Published
path-to-regexp vulnerable to Regular Expression Denial of Service via multiple wildcards
cve-program · CVE-2026-4923 · Published