CVE-2026-33750

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

Published Mar 27, 2026 CVSS 3.1 · 6.5 Medium EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-f886-m6hf-6m8v brace-expansion: Zero-step sequence causes process hang and memory exhaustion
History
Type Values Removed Values Added
CPEs cpe:2.3:a:juliangruber:brace-expansion:*:*:*:*:*:node.js:*:*
Type Values Removed Values Added
First Time appeared Juliangruber
Juliangruber brace-expansion
Vendors & Products Juliangruber
Juliangruber brace-expansion
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description 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.
Title brace-expansion: Zero-step sequence causes process hang and memory exhaustion
Weaknesses CWE-400
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Mar 27, 2026, 2:48 PM
Reserved
Mar 23, 2026, 6:30 PM
Status
Analyzed
Published
Mar 27, 2026, 3:16 PM
Modified
Oct 26, 2026, 10:10 PM
Severity
Moderate
Public date
Mar 27, 2026, 2:04 PM