How severe is CVE-2020-7760?

CVE-2020-7760 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2020-7760?

CVE-2020-7760 affects the following packages: codemirror (npm). Ecosystems affected: npm.

How do I fix CVE-2020-7760?

Update codemirror to 5.58.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-7760 is resolved across your whole dependency graph.

How do I detect CVE-2020-7760 in my npm dependencies?

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.

How do I mitigate CVE-2020-7760 if there is no patch (or I can't update yet)?

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 does O3 Security protect against CVE-2020-7760?

O3 pinpoints whether CVE-2020-7760 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2020-7760 actively exploited in the wild?

Yes. There are 7 known exploit references for CVE-2020-7760, including 7 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What type of vulnerability is CVE-2020-7760?

CVE-2020-7760 is classified as Uncontrolled Resource Consumption (CWE-400). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2020-7760 published, and has it been updated?

CVE-2020-7760 was published on October 30, 2020 and was last updated on August 27, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦

📦 npm

Not in CISA KEV

HIGH severity

CVE-2020-7760

HIGHFix: codemirror/CodeMirror@55d0333

CVE-2020-7760 is a high-severity (CVSS 7.5) Uncontrolled Resource Consumption vulnerability in codemirror. 7 public exploit references exist, so weaponization risk is real. O3 Security confirms whether CVE-2020-7760 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

Regular expression denial of service in codemirror

Also known asGHSA-4gw3-8f77-f72c

Published

Oct 30, 2020

Updated

Aug 27, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

7 known

Exploitation data as of Aug 27, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Real-World Exposure

1 pkg affected

📦codemirror

Real-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

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`codemirror`	all versions	5.58.2

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.