CVE-2026-33671 | Picomatch has a ReDoS vulnerability via extglob quantifiers

Picomatch is a glob matcher written JavaScript. Versions prior to 4.0.4, 3.0.2, and 2.3.2 are vulnerable to Regular Expression Denial of Service (ReDoS) when processing crafted extglob patterns. Certain patterns using extglob quantifiers such as `+()` and `*()`, especially when combined with overlapping alternatives or nested extglobs, are compiled into regular expressions that can exhibit catastrophic backtracking on non-matching input. Applications are impacted when they allow untrusted users to supply glob patterns that are passed to `picomatch` for compilation or matching. In those cases, an attacker can cause excessive CPU consumption and block the Node.js event loop, resulting in a denial of service. Applications that only use trusted, developer-controlled glob patterns are much less likely to be exposed in a security-relevant way. This issue is fixed in picomatch 4.0.4, 3.0.2 and 2.3.2. Users should upgrade to one of these versions or later, depending on their supported release line. If upgrading is not immediately possible, avoid passing untrusted glob patterns to `picomatch`. Possible mitigations include disabling extglob support for untrusted patterns by using `noextglob: true`, rejecting or sanitizing patterns containing nested extglobs or extglob quantifiers such as `+()` and `*()`, enforcing strict allowlists for accepted pattern syntax, running matching in an isolated worker or separate process with time and resource limits, and applying application-level request throttling and input validation for any endpoint that accepts glob patterns.

Published: 2026-03-26 Last update: 2026-04-01 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-33671 is rated Low Risk (31.6/100): CVSS High severity, with low exploitation likelihood (EPSS 0.02%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-33671

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-21 0.05% 0.02% -0.03%
2 2026-04-01 0.04% 0.05% +0.01%
3 2026-03-27 0.04%

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-33671

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 3.6 [email protected]

Weakness enumeration for CVE-2026-33671

GitHub Security Advisory for CVE-2026-33671

GHSA-c2c7-rcm5-vvqj · Severity: high · Ecosystem: npm — Picomatch has a ReDoS vulnerability via extglob quantifiers

OS Trackers for CVE-2026-33671

vendor priority summary link
debian not yet assigned CVE-2026-33671 not yet assigned priority: Debian including 1 source packages (node-anymatch), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-33671
redhat medium https://access.redhat.com/security/cve/CVE-2026-33671
ubuntu medium CVE-2026-33671 medium priority: Ubuntu including 1 source packages (node-anymatch), 6 status rows across 6 suites (bionic, focal, jammy, noble, questing, upstream): needs-triage 5, released 1. https://ubuntu.com/security/CVE-2026-33671

Affected software / configurations for CVE-2026-33671

Vendor Product Version Raw CPE
jonschlinkert picomatch < 2.3.2 cpe:2.3:a:jonschlinkert:picomatch:*:*:*:*:*:node.js:*:*
jonschlinkert picomatch >= 3.0.0, < 3.0.2 cpe:2.3:a:jonschlinkert:picomatch:*:*:*:*:*:node.js:*:*
jonschlinkert picomatch >= 4.0.0, < 4.0.4 cpe:2.3:a:jonschlinkert:picomatch:*:*:*:*:*:node.js:*:*

References for CVE-2026-33671

cvelogic Threat Intelligence