CVE-2026-45149

Description

The brace-expansion library generates arbitrary strings containing a common prefix and suffix. From 5.0.0 to before 5.0.6, the max option was being applied too late. When expanding a single large numeric range like {1..10000000}, the sequence generation loop generates all 10 million intermediate elements before the max limit is applied With max=10, the output is correctly limited to 10 items, but the process still allocates ~505 MB and spends ~800ms building the full intermediate array. This vulnerability is fixed in 5.0.6.

CVSS Metrics

• v3.1•MEDIUM•Score: 6.5CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
• v3.1•HIGH•Score: 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Trends

Current EPSS score: 0.28%• Percentile: 20%

Techniques & Countermeasures

• CWE-400•Uncontrolled Resource Consumption

  The product does not properly control the allocation and maintenance of a limited resource.

Affected Systems

• juliangruber•brace-expansion

  ≥ 5.0.0, ≤ 5.0.6 | ≥ 5.0.0, < 5.0.6

• Npm•brace-expansion

  ≥ 5.0.0, < 5.0.6

References (4)

• https://github.com/juliangruber/brace-expansion/security/advisories/GHSA-jxxr-4gwj-5jf2
• https://github.com/juliangruber/brace-expansion/commit/c0b095bdc52bc4c36dc88deddbadabc49f8371e5
• https://github.com/juliangruber/brace-expansion
• https://nvd.nist.gov/vuln/detail/CVE-2026-45149