# CVE-2026-33750: brace-expansion: Zero-step sequence causes process hang and memory exhaustion

> CVE-2026-33750: brace-expansion: Zero-step sequence causes process hang and memory exhaustion. CVSS 6.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-33750
Last updated: 2026-06-17T10:38:02Z

- Published: 2026-03-27 14:04 UTC · Updated: 2026-06-17 10:38 UTC · Assigner: GitHub\_M
- CVSS: 6.5 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
- EPSS: 0.45%, 39th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-400

## 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 vendors and products

- juliangruber: brace-expansion

## Tracked companies

- [Bitbucket](https://rewindex.com/company/bitbucket.md)
- [Confluence](https://rewindex.com/company/confluence.md)
- [Jira](https://rewindex.com/company/jira.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-33750)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-33750)
- [https://github.com/juliangruber/brace-expansion/blob/daa71bcb4a30a2df9bcb7f7b8daaf2ab30e5794a/src/index.ts\#L107-L113](https://github.com/juliangruber/brace-expansion/blob/daa71bcb4a30a2df9bcb7f7b8daaf2ab30e5794a/src/index.ts#L107-L113)
- [https://github.com/juliangruber/brace-expansion/blob/daa71bcb4a30a2df9bcb7f7b8daaf2ab30e5794a/src/index.ts\#L184](https://github.com/juliangruber/brace-expansion/blob/daa71bcb4a30a2df9bcb7f7b8daaf2ab30e5794a/src/index.ts#L184)
- [https://github.com/juliangruber/brace-expansion/commit/311ac0d54994158c0a384e286a7d6cbb17ee8ed5](https://github.com/juliangruber/brace-expansion/commit/311ac0d54994158c0a384e286a7d6cbb17ee8ed5)
- [https://github.com/juliangruber/brace-expansion/commit/7fd684f89fdde3549563d0a6522226a9189472a2](https://github.com/juliangruber/brace-expansion/commit/7fd684f89fdde3549563d0a6522226a9189472a2)
- [https://github.com/juliangruber/brace-expansion/commit/b9cacd9e55e7a1fa588fe4b7bb1159d52f1d902a](https://github.com/juliangruber/brace-expansion/commit/b9cacd9e55e7a1fa588fe4b7bb1159d52f1d902a)
- [https://github.com/juliangruber/brace-expansion/issues/98](https://github.com/juliangruber/brace-expansion/issues/98)
- [https://github.com/juliangruber/brace-expansion/pull/95](https://github.com/juliangruber/brace-expansion/pull/95)
- [https://github.com/juliangruber/brace-expansion/pull/96](https://github.com/juliangruber/brace-expansion/pull/96)
- [https://github.com/juliangruber/brace-expansion/pull/97](https://github.com/juliangruber/brace-expansion/pull/97)
- [https://github.com/juliangruber/brace-expansion/security/advisories/GHSA-f886-m6hf-6m8v](https://github.com/juliangruber/brace-expansion/security/advisories/GHSA-f886-m6hf-6m8v)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-33750 · Markdown: https://rewindex.com/cve/CVE-2026-33750.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-33750 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:16:38.711Z