CVE-2026-13311: Shell-Quote Project Shell-Quote

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

shell-quote prior to 1.8.5 finalizes parsed tokens in parse() using Array.prototype.concat as a reduce accumulator, which reallocates and copies the entire growing array on every iteration. As a result parse() runs in O(n^2) time relative to the number of input tokens. An attacker who can supply an attacker-controlled string to any code path that calls parse() (no shell metacharacters are required; plain space-separated words suffice) can block the single-threaded Node.js event loop for an extended period with a small input, resulting in a denial of service. There is no code execution or data disclosure; impact is to availability only. Fixed in 1.8.5.

Affected products

Published 2026-06-25. Last modified 2026-06-26.