MediumGHSA-952p-6rrq-rcjvCVE-2024-4067

Regular Expression Denial of Service (ReDoS) in micromatch

Published 14 May 2024 · Updated 10 Sept 2026

Affected package

Affected
<4.0.8
Fixed in
4.0.8
Update to the fixed version for your release line, for example:npm install micromatch@4.0.8

Details

The NPM package micromatch prior to version 4.0.8 is vulnerable to Regular Expression Denial of Service (ReDoS). The vulnerability occurs in micromatch.braces() in index.js because the pattern .* will greedily match anything. By passing a malicious payload, the pattern matching will keep backtracking to the input while it doesn't find the closing bracket. As the input size increases, the consumption time will also increase until it causes the application to hang or slow down. There was a merged fix but further testing shows the issue persisted prior to https://github.com/micromatch/micromatch/pull/266. This issue should be mitigated by using a safe pattern that won't start backtracking the regular expression due to greedy matching.

Is GHSA-952p-6rrq-rcjv in any of your client repos?

Checking one package by hand is fine. Checking it across forty client projects is not. NPMscan reads the lockfiles in every GitHub repo you pick, finds each project with an affected micromatch, and gives you the command that fixes it.

References

Advisory data from OSV.dev (opens OSV.dev in a new tab), refreshed daily.