Medium 6.5Published Mar 27, 2026

CVE-2026-33750brace-expansion: Zero-step sequence causes process hang and memory exhaustion

Updated under an hour ago (Oct 28, 2026, 12:40 AM ET)

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Every CVE for juliangruber brace-expansion

Exploited in the last 30 days

The brace-expansion library generates arbitrary strings containing a common prefix and suffix. Prior to versions 5.0.5, 3.0.2, 2.0.3, and 1.1.13, a brace pattern with a zero step value (e.g., `{1..2..0}`) causes the sequence generation loop to run indefinitely, making the process hang for seconds and allocate heaps of memory. Versions 5.0.5, 3.0.2, 2.0.3, and 1.1.13 fix the issue. As a workaround, sanitize strings passed to `expand()` to ensure a step value of `0` is not used.

CVSS: 6.5 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-400
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Mar 27, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

juliangruber brace-expansion juliangruber:brace_expansion (from the name)	from 4.0.0, < 5.0.5; from 3.0.0, < 3.0.2; from 2.0.0, < 2.0.3; before 1.1.13	CNA record
juliangruber brace-expansion juliangruber:brace-expansion	before 1.1.13; from 2.0.0 before 2.0.3; from 3.0.0 before 3.0.2; from 5.0.0 before 5.0.5	NVD

References

References

https://github.com/juliangruber/brace-expansion/security/advisories/GHSA-f886-m6hf-6m8v	x-refsource-confirm, mitigation, vendor-advisory
https://github.com/juliangruber/brace-expansion/issues/98	x-refsource-misc, issue-tracking
https://github.com/juliangruber/brace-expansion/pull/95	x-refsource-misc, issue-tracking, patch
https://github.com/juliangruber/brace-expansion/pull/96	x-refsource-misc, issue-tracking, patch
https://github.com/juliangruber/brace-expansion/pull/97	x-refsource-misc, issue-tracking, patch
https://github.com/juliangruber/brace-expansion/commit/311ac0d54994158c0a384e286a7d6cbb17ee8ed5	x-refsource-misc, patch
https://github.com/juliangruber/brace-expansion/commit/7fd684f89fdde3549563d0a6522226a9189472a2	x-refsource-misc, patch
https://github.com/juliangruber/brace-expansion/commit/b9cacd9e55e7a1fa588fe4b7bb1159d52f1d902a	x-refsource-misc, patch
https://github.com/juliangruber/brace-expansion/blob/daa71bcb4a30a2df9bcb7f7b8daaf2ab30e5794a/src/index.ts#L107-L113	x-refsource-misc, patch
https://github.com/juliangruber/brace-expansion/blob/daa71bcb4a30a2df9bcb7f7b8daaf2ab30e5794a/src/index.ts#L184	x-refsource-misc, patch

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.