GHSA-37ch-88jc-xwx2 — path-to-regexp
HIGHGHSA-37ch-88jc-xwx2 is a high-severity (CVSS 7.5) CWE-1333 vulnerability in path-to-regexp. A fix is available for path-to-regexp — see the affected versions and patch details below.
path-to-regexp vulnerable to Regular Expression Denial of Service via multiple route parameters
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-37ch-88jc-xwx2.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-37ch-88jc-xwx2 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
path-to-regexpnpmDescription
Impact
A bad regular expression is generated any time you have three or more parameters within a single segment, separated by something that is not a period (.). For example, /:a-:b-:c or /:a-:b-:c-:d. The backtrack protection added in [email protected] only prevents ambiguity for two parameters. With three or more, the generated lookahead does not block single separator characters, so capture groups overlap and cause catastrophic backtracking.
Patches
Upgrade to [email protected]
Custom regex patterns in route definitions (e.g., /:a-:b([^-/]+)-:c([^-/]+)) are not affected because they override the default capture group.
Workarounds
All versions can be patched by providing a custom regular expression for parameters after the first in a single segment. As long as the custom regular expression does not match the text before the parameter, you will be safe. For example, change /:a-:b-:c to /:a-:b([^-/]+)-:c([^-/]+).
If paths cannot be rewritten and versions cannot be upgraded, another alternative is to limit the URL length.
References
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | path-to-regexp | all versions | 0.1.13npm install path-to-regexp@0.1.13 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for path-to-regexp, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update path-to-regexp to 0.1.13 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-37ch-88jc-xwx2 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-37ch-88jc-xwx2 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-37ch-88jc-xwx2. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
| Product | Fixed in | Advisory |
|---|---|---|
| Discovery 1 for RHEL 9 | discovery/discovery-server-rhel9:1.12.0-1 | RHSA-2025:1249 |
| HawtIO 4.0.0 for Red Hat build of Apache Camel 4 | path-to-regexp | RHSA-2024:11023 |
| multicluster engine for Kubernetes 2.6 for RHEL 8 | multicluster-engine/assisted-image-service-rhel8:v2.6.4-4 | RHSA-2024:11293 |
| multicluster engine for Kubernetes 2.7 for RHEL 8 | multicluster-engine/assisted-service-8-rhel8:v2.7.2-1 | RHSA-2024:10857 |
| NETWORK-OBSERVABILITY-1.7.0-RHEL-9 | network-observability/network-observability-cli-rhel9:v1.7.0-67 | RHSA-2024:8014 |
| Red Hat Advanced Cluster Management for Kubernetes 2.11 for RHEL 9 | rhacm2/acm-cluster-permission-rhel9:v2.11.4-4 | RHSA-2024:11381 |
| Red Hat Advanced Cluster Management for Kubernetes 2.12 for RHEL 9 | rhacm2/acm-cli-rhel9:v2.12.1-4 | RHSA-2024:10865 |
| Red Hat Ansible Automation Platform 2.4 for RHEL 8 | automation-controller-0:4.5.13-1.el8ap | RHSA-2024:10762 |
Frequently Asked Questions
Is GHSA-37ch-88jc-xwx2 in your dependencies?
O3 Security finds GHSA-37ch-88jc-xwx2 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.