Resource exhaustion in Juliangruber Brace-Expansion
CVE-2026-33750
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.
Vulnerability class: DoS (Denial of Service)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.006 (49.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 50th percentile — 49.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: +0.000
Affected products
- Juliangruber Brace-Expansion — versions >= 4.0.0, < 5.0.5, >= 3.0.0, < 3.0.2, >= 2.0.0, < 2.0.3
Weakness classification (CWE)
References
- github.com/juliangruber/brace-expansion/security/advisories/GHSA-f886-m6hf-6m8v (Mitigation, Vendor Advisory)
- github.com/juliangruber/brace-expansion/issues/98 (Issue Tracking)
- github.com/juliangruber/brace-expansion/pull/95 (Patch, Issue Tracking)
- github.com/juliangruber/brace-expansion/pull/96 (Patch, Issue Tracking)
- github.com/juliangruber/brace-expansion/pull/97 (Patch, Issue Tracking)
- github.com/juliangruber/brace-expansion/commit/311ac0d54994158c0a384e286a7d6cbb… (Patch)
- github.com/juliangruber/brace-expansion/commit/7fd684f89fdde3549563d0a6522226a9… (Patch)
- github.com/juliangruber/brace-expansion/commit/b9cacd9e55e7a1fa588fe4b7bb1159d5… (Patch)
- github.com/juliangruber/brace-expansion/blob/daa71bcb4a30a2df9bcb7f7b8daaf2ab30… (Patch)
- github.com/juliangruber/brace-expansion/blob/daa71bcb4a30a2df9bcb7f7b8daaf2ab30… (Patch)
Frequently asked questions
- What is CVE-2026-33750?
- CVE-2026-33750 is a medium-severity vulnerability in Juliangruber Brace-Expansion, classified under Uncontrolled Resource Consumption. CVSS score: 6.5/10. Published 2026-03-27.
- How severe is CVE-2026-33750?
- Medium severity. CVSS v3 base score is 6.5 out of 10.