CVE-2022-21680 is a high-severity (CVSS 7.5) Uncontrolled Resource Consumption vulnerability in marked. 1 public exploit reference exists, so weaponization risk is real. O3 Security confirms whether CVE-2022-21680 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Cubic catastrophic backtracking (ReDoS) in marked
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, a proxy for how much of the ecosystem is exposed.
markednpmDescription
Marked is a markdown parser and compiler. Prior to version 4.0.10, the regular expression block.def may cause catastrophic backtracking against some strings and lead to a regular expression denial of service (ReDoS). Anyone who runs untrusted markdown through a vulnerable version of marked and does not use a worker with a time limit may be affected. This issue is patched in version 4.0.10. As a workaround, avoid running untrusted markdown through marked or run marked on a worker thread and set a reasonable time limit to prevent draining resources.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | marked | all versions | 4.0.10 |
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 marked. 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 marked to 4.0.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-21680 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 CVE-2022-21680 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 CVE-2022-21680. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2022-21680 in your dependencies?
O3 detects CVE-2022-21680 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.