path-to-regexp vulnerable to Regular Expression Denial of Service via multiple wildcards
### 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.
describes (1)
Related CVEs.
| ID | severity | exploitable | ||
|---|---|---|---|---|
| CVE-2026-4923US | — | — | ||
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 req… | ||||
references
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