CVE-2019-11837: F5 Njs

High severity, CVSS 7.5. EPSS: 1.4% chance of exploitation in the next 30 days.

njs through 0.3.1, used in NGINX, has a segmentation fault in String.prototype.toBytes for negative arguments, related to nxt_utf8_next in nxt/nxt_utf8.h and njs_string_offset in njs/njs_string.c.

Affected products

• F5 Njs: up to and including 0.3.1

Published 2019-05-09. Last modified 2026-06-17.