GHSA-j3q9-mxjg-w52f
path-to-regexp vulnerable to Denial of Service via sequential optional groups
At a glance
- Published
- Updated
- CVE
- CVE-2026-4926
- CVSS_V3
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Description
### Impact A bad regular expression is generated any time you have multiple sequential optional groups (curly brace syntax), such as `{a}{b}{c}:z`. The generated regex grows exponentially with the number of groups, causing denial of service. ### Patches Fixed in version 8.4.0. ### Workarounds Limit the number of sequential optional groups in route patterns. Avoid passing user-controlled input as route patterns.
Affected packages
| Package | Versions |
|---|---|
| npm · path-to-regexp | introduced 8.0.0, fixed 8.4.0 |
References
- https://github.com/pillarjs/path-to-regexp/security/advisories/GHSA-j3q9-mxjg-w52f WEB
- https://nvd.nist.gov/vuln/detail/CVE-2026-4926 ADVISORY
- https://cna.openjsf.org/security-advisories.html WEB
- https://github.com/pillarjs/path-to-regexp PACKAGE
Sources
| Source | Licence |
|---|---|
| OSV.dev | CC-BY 4.0 — GitHub Advisory Database |