CVE-2026-33750

MEDIUM 6.5

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

CVSS Score

6.5

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-400
Vendor	juliangruber
Product	brace-expansion
Published	Mar 27, 2026
Last Updated	Mar 27, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Affected Versions

juliangruber / brace-expansion

>= 4.0.0, < 5.0.5 >= 3.0.0, < 3.0.2 >= 2.0.0, < 2.0.3 < 1.1.13

References

NVD ↗ CVE.org ↗ EPSS Data ↗