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.
Affected products
juliangruber: brace-expansion
References10
- github.com/juliangruber/brace-expansion/security/advisories/GHS… MitigationVendor Advisory
- github.com/juliangruber/brace-expansion/blob/daa71bcb4a30a2df9b… Patch
- github.com/juliangruber/brace-expansion/blob/daa71bcb4a30a2df9b… Patch
- github.com/juliangruber/brace-expansion/commit/311ac0d54994158c… Patch
- github.com/juliangruber/brace-expansion/commit/7fd684f89fdde354… Patch
- github.com/juliangruber/brace-expansion/commit/b9cacd9e55e7a1fa… Patch
- github.com/juliangruber/brace-expansion/pull/95 Issue TrackingPatch
- github.com/juliangruber/brace-expansion/pull/96 Issue TrackingPatch
- github.com/juliangruber/brace-expansion/pull/97 Issue TrackingPatch
- github.com/juliangruber/brace-expansion/issues/98 Issue Tracking
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 39 · as of 12 November 2026
- CWE
- CWE-400
Could this be exploited in your environment?
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