CVE-2026-33750: brace-expansion: Zero-step sequence causes process hang and memory exhaustion
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.
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H · CWE-400
Tracked companies
Mapped from the CVE’s affected-product data, NVD CPE matches, vendor advisories or package feeds. A mapping means the vendor’s software is named, not that its hosted service was exposed.
Status incidents that name it
No tracked status incident names this CVE.
Affected vendors and products
juliangruber: brace-expansion
References
- CVE record on cve.org (opens in new tab)
- NVD entry (opens in new tab)
- github.com/juliangruber/brace-expansion/blob/daa71bcb4a30a2df9bcb7f7b8daaf2ab30e… (opens in new tab)
- github.com/juliangruber/brace-expansion/blob/daa71bcb4a30a2df9bcb7f7b8daaf2ab30e… (opens in new tab)
- github.com/juliangruber/brace-expansion/commit/311ac0d54994158c0a384e286a7d6cbb1… (opens in new tab)
- github.com/juliangruber/brace-expansion/commit/7fd684f89fdde3549563d0a6522226a91… (opens in new tab)
- github.com/juliangruber/brace-expansion/commit/b9cacd9e55e7a1fa588fe4b7bb1159d52… (opens in new tab)
- github.com/juliangruber/brace-expansion/issues/98 (opens in new tab)
- github.com/juliangruber/brace-expansion/pull/95 (opens in new tab)
- github.com/juliangruber/brace-expansion/pull/96 (opens in new tab)
- github.com/juliangruber/brace-expansion/pull/97 (opens in new tab)
- github.com/juliangruber/brace-expansion/security/advisories/GHSA-f886-m6hf-6m8v (opens in new tab)
- CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (opens in new tab)
- This product uses data from the NVD API but is not endorsed or certified by the NVD. (opens in new tab)
- Known Exploited Vulnerabilities catalog from CISA. (opens in new tab)
- EPSS scores from FIRST (Exploit Prediction Scoring System). (opens in new tab)