CVE-2026-14257 PUBLISHED

brace-expansion DoS via unbounded expansion length causing an out-of-memory process crash

Assigner: seal
Reserved: 30.06.2026 Published: 23.07.2026 Updated: 23.07.2026

brace-expansion through 5.0.7 is vulnerable to denial of service via memory exhaustion. The expand() function limits the number of results with a max option (default 100,000) but does not bound the length of each result string. By chaining multiple brace groups, an attacker keeps the result count under the limit while making each result progressively longer, so total memory scales with both count and string length until the process hits a fatal, uncatchable out-of-memory error. About 7.5 KB of input ('{a,b}'.repeat(1500)) crashes a default Node.js process. Any application that passes attacker-influenced strings to brace-expansion.expand() - directly or transitively via minimatch / glob brace patterns - can be crashed by a small request. Fixed in 5.0.8 by adding a maxLength option (default 4,000,000) that bounds accumulated output and intermediate arrays.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS Score: 7.5

Product Status

Vendor juliangruber
Product brace-expansion
Versions Default: unaffected
  • affected from 0 to 5.0.7 (incl.)

Credits

  • bnbdr finder

References

Problem Types

  • CWE-400 Uncontrolled Resource Consumption CWE
  • CWE-770 Allocation of Resources Without Limits or Throttling CWE

Impacts

  • CAPEC-469 HTTP DoS