How severe is GHSA-44c6-4v22-4mhx?

GHSA-44c6-4v22-4mhx has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by GHSA-44c6-4v22-4mhx?

GHSA-44c6-4v22-4mhx affects the following packages: semver-regex (npm), semver-regex (npm). Ecosystems affected: npm.

How do I fix GHSA-44c6-4v22-4mhx?

Update semver-regex to 3.1.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-44c6-4v22-4mhx is resolved across your whole dependency graph.

How do I detect GHSA-44c6-4v22-4mhx in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for semver-regex. 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 GHSA-44c6-4v22-4mhx 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 GHSA-44c6-4v22-4mhx?

O3 pinpoints whether GHSA-44c6-4v22-4mhx 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 GHSA-44c6-4v22-4mhx actively exploited in the wild?

Yes. There are 1 known exploit references for GHSA-44c6-4v22-4mhx, including 1 in-the-wild exploitation 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 is the EPSS score for GHSA-44c6-4v22-4mhx?

GHSA-44c6-4v22-4mhx has an EPSS (Exploit Prediction Scoring System) score of 1.4%, placing it in the 69th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

When was GHSA-44c6-4v22-4mhx published, and has it been updated?

GHSA-44c6-4v22-4mhx was published on September 20, 2021 and was last updated on February 4, 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

GHSA-44c6-4v22-4mhx

HIGH

semver-regex Regular Expression Denial of Service (ReDOS)

Also known asCVE-2021-3795

Published

Sep 20, 2021

Updated

Feb 4, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

1 known

EPSS Exploitation Probability

via FIRST.org ↗

1.4%probability of exploitation in next 30 days

Lower Risk69th percentile+0.94%

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.

Blast Radius

2 pkgs affected

Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.

semver-regexnpm

9.0Mdownloads / week

Description

npm semver-regex is vulnerable to Inefficient Regular Expression Complexity

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`semver-regex`	all versions	3.1.3
📦npm	`semver-regex`	≥ 4.0.0&&< 4.0.1	4.0.1

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.

semver-regex is vulnerable to Inefficient Regular Expression Complexity

huntr.devNVDSep 2021

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for semver-regex. 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 semver-regex to 3.1.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-44c6-4v22-4mhx 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-44c6-4v22-4mhx 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-44c6-4v22-4mhx. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

npm `semver-regex` is vulnerable to Inefficient Regular Expression Complexity

O3 Security · Impact-Aware SCA

Is GHSA-44c6-4v22-4mhx in your dependencies?

O3 detects GHSA-44c6-4v22-4mhx across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works