Regular Expression Denial of Service in Picomatch by Micromatch
CVE-2026-112366

8.7HIGH

Key Information:

Vendor

Micromatch

Status
Picomatch
Vendor
CVE Published:
19 October 2026

What is CVE-2026-112366?

Picomatch versions up to 4.0.7 contain a vulnerability that allows attackers to exploit regular expression processing. By using specially crafted single-branch repeated extglob patterns, such as +(*) or +(*a), attackers can block the event loop, leading to potential denial of service in Node.js applications. The vulnerable code in lib/parse.js fails to handle these patterns properly, resulting in exponential backtracking and resource exhaustion.

Affected Version(s)

picomatch 0 <= 4.0.7

References

https://github.com/micromatch/picomatch/pull/194
patchissue-tracking
https://github.com/micromatch/picomatch/blob/4.0.7/lib/pa...
technical-description
https://www.vulncheck.com/advisories/picomatch-through-4....
third-party-advisory

CVSS V4

Score:
8.7
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

maximilliangrand
Zachariah Mithani
.