CVE-2026-25547

CVE-2026-25547 describes a critical denial-of-service vulnerability in @isaacs/brace-expansion versions prior to 5.0.1, affecting Node.js applications that utilize this library. The flaw, categorized as CWE-1333 (Inefficient Regular Expression Complexity), allows an attacker to provide specially crafted input with repeated numeric brace ranges. This input triggers an exponential expansion of combinations, consuming excessive CPU and memory and potentially crashing the Node.js process. Rated with a CVSS score of 9.2 (CRITICAL), this vulnerability has a network attack vector, low attack complexity, and no user interaction required, leading to high availability impact. While there is no evidence of active exploitation, exploit code availability (Metasploit, Nuclei, ExploitDB) is currently none. However, the vulnerability has garnered significant community attention with 4 mentions and 4 media articles, indicating awareness and potential for future exploitation.