GHSA-4gw3-8f77-f72c is a medium-severity (CVSS 5.3) Uncontrolled Resource Consumption vulnerability in codemirror. 7 public exploit references exist, so weaponization risk is real. O3 Security confirms whether GHSA-4gw3-8f77-f72c is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Regular expression denial of service in codemirror
Real-World Exposure
codemirrorReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.
Description
This affects the package codemirror before 5.58.2; the package org.apache.marmotta.webjars:codemirror before 5.58.2. The vulnerable regular expression is located in https://github.com/codemirror/CodeMirror/blob/cdb228ac736369c685865b122b736cd0d397836c/mode/javascript/javascript.jsL129. The ReDOS vulnerability of the regex is mainly due to the sub-pattern (s|/.?/)
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | codemirror | all versions | 5.58.2 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
This affects the package codemirror before 5.58.2; the package org.apach…
This affects the package codemirror before 5.58.2; the package org.apach…
This affects the package codemirror before 5.58.2; the package org.apach…
This affects the package codemirror before 5.58.2; the package org.apach…
This affects the package codemirror before 5.58.2; the package org.apach…
This affects the package codemirror before 5.58.2; the package org.apach…
This affects the package codemirror before 5.58.2; the package org.apach…
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for codemirror. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update codemirror to 5.58.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4gw3-8f77-f72c 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 pinpoints whether GHSA-4gw3-8f77-f72c is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-4gw3-8f77-f72c. 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-4gw3-8f77-f72c in your dependencies?
O3 detects GHSA-4gw3-8f77-f72c across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.