CVE-2026-22184: Zlib

High severity, CVSS 7.8. EPSS: 0.4% chance of exploitation in the next 30 days.

zlib versions up to and including 1.3.1.2 include a global buffer overflow in the untgz utility located under contrib/untgz. The vulnerability is limited to the standalone demonstration utility and does not affect the core zlib compression library. The flaw occurs when a user executes the untgz command with an excessively long archive name supplied via the command line, leading to an out-of-bounds write in a fixed-size global buffer.

Affected products

• Zlib Zlib: up to and including 1.3.1.2

Published 2026-01-07. Last modified 2026-09-01.