CVE-2026-45149: Juliangruber Brace-Expansion

High severity, CVSS 7.5. EPSS: 0.4% chance of exploitation in the next 30 days.

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.

Affected products

• Juliangruber Brace-Expansion: from 5.0.0, before 5.0.6 (fixed in 5.0.6)

Published 2026-05-29. Last modified 2026-07-22.