The brace-expansion library generates arbitrary strings containing a common prefix and suffix. Prior to 1.1.18, 2.1.4, 3.0.6, and 5.0.9, expand() does not apply maxLength while constructing comma-alternative intermediate arrays or padded sequences, allowing attacker-controlled input to exhaust memory or block the event loop. The fix for CVE-2026-14257 is bypassed by the vulnerability. This issue is fixed in versions 1.1.18, 2.1.4, 3.0.6, and 5.0.9.
Analyzing vulnerability vectors…