GHSA-c2c7-rcm5-vvqj is a high-severity (CVSS 7.5) CWE-1333 vulnerability in picomatch. A fix is available for picomatch — see the affected versions and patch details below.
Picomatch has a ReDoS vulnerability via extglob quantifiers
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-c2c7-rcm5-vvqj.
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-c2c7-rcm5-vvqj 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 377,238 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.
picomatchnpmDescription
Impact
picomatch is vulnerable to Regular Expression Denial of Service (ReDoS) when processing crafted extglob patterns. Certain patterns using extglob quantifiers such as +() and *(), especially when combined with overlapping alternatives or nested extglobs, are compiled into regular expressions that can exhibit catastrophic backtracking on non-matching input.
Examples of problematic patterns include +(a|aa), +(*|?), +(+(a)), *(+(a)), and +(+(+(a))). In local reproduction, these patterns caused multi-second event-loop blocking with relatively short inputs. For example, +(a|aa) compiled to ^(?:(?=.)(?:a|aa)+)$ and took about 2 seconds to reject a 41-character non-matching input, while nested patterns such as +(+(a)) and *(+(a)) took around 29 seconds to reject a 33-character input on a modern M1 MacBook.
Applications are impacted when they allow untrusted users to supply glob patterns that are passed to picomatch for compilation or matching. In those cases, an attacker can cause excessive CPU consumption and block the Node.js event loop, resulting in a denial of service. Applications that only use trusted, developer-controlled glob patterns are much less likely to be exposed in a security-relevant way.
Patches
This issue is fixed in picomatch 4.0.4, 3.0.2 and 2.3.2.
Users should upgrade to one of these versions or later, depending on their supported release line.
Workarounds
If upgrading is not immediately possible, avoid passing untrusted glob patterns to picomatch.
Possible mitigations include:
- disable extglob support for untrusted patterns by using
noextglob: true - reject or sanitize patterns containing nested extglobs or extglob quantifiers such as
+()and*() - enforce strict allowlists for accepted pattern syntax
- run matching in an isolated worker or separate process with time and resource limits
- apply application-level request throttling and input validation for any endpoint that accepts glob patterns
Resources
- Picomatch repository: https://github.com/micromatch/picomatch
lib/parse.jsandlib/constants.jsare involved in generating the vulnerable regex forms- Comparable ReDoS precedent: CVE-2024-4067 (
micromatch) - Comparable generated-regex precedent: CVE-2024-45296 (
path-to-regexp)
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | picomatch | ≥ 4.0.0&&< 4.0.4 | 4.0.4npm install picomatch@4.0.4 |
| 📦npm | picomatch | ≥ 3.0.0&&< 3.0.2 | 3.0.2npm install picomatch@3.0.2 |
| 📦npm | picomatch | all versions | 2.3.2npm install picomatch@2.3.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for picomatch, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update picomatch to 4.0.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-c2c7-rcm5-vvqj 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-c2c7-rcm5-vvqj can be triaged on real exposure rather than presence alone.
Tailored to GHSA-c2c7-rcm5-vvqj. 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 |
|---|---|---|
| Cluster Observability Operator 1.5.0 | cluster-observability-operator/logging-console-plugin-pf4-rhel9:1782839279 | RHSA-2026:34342 |
| Red Hat Openshift Data Foundation 4.18 | odf4/cephcsi-rhel9:1786705347 | RHSA-2026:56431 |
| Red Hat Openshift Data Foundation 4.22 | odf4/cephcsi-rhel9:1787057250 | RHSA-2026:56928 |
Frequently Asked Questions
Is GHSA-c2c7-rcm5-vvqj in your dependencies?
O3 Security finds GHSA-c2c7-rcm5-vvqj across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.