GHSA-xrx9-gj26-5wx9 is a high-severity (CVSS 7.5) Uncontrolled Resource Consumption vulnerability in v8n. 1 public exploit reference exists, so weaponization risk is real. A fix is available for v8n — see the affected versions and patch details below.
v8n vulnerable to Inefficient Regular Expression Complexity
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for GHSA-xrx9-gj26-5wx9.
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-xrx9-gj26-5wx9 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.
v8nnpmDescription
Impact
Inefficient regular expression complexity of lowercase() and uppercase() regex could lead to a denial of service attack. With a formed payload 'a' + 'a'.repeat(i) + 'A', only 32 characters payload could take 29443 ms time execution when testing lowercase(). The same issue happens with uppercase().
Patches
v1.5.1
References
huntr.dev report Regular Expression Denial of Service (ReDoS) and Catastrophic Backtracking
For more information
If you have any questions or comments about this advisory:
- Open an issue in v8n issues list
- Email us at [email protected]
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | v8n | all versions | 1.5.1npm install v8n@1.5.1 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for v8n, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update v8n to 1.5.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-xrx9-gj26-5wx9 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-xrx9-gj26-5wx9 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-xrx9-gj26-5wx9. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-xrx9-gj26-5wx9 in your dependencies?
O3 Security finds GHSA-xrx9-gj26-5wx9 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.