CVE-2026-22184

Publication date 8 January 2026

Last updated 8 January 2026


Ubuntu priority

Description

zlib versions up to and including 1.3.1.2 contain a global buffer overflow in the untgz utility. The TGZfname() function copies an attacker-supplied archive name from argv[] into a fixed-size 1024-byte static global buffer using an unbounded strcpy() call without length validation. Supplying an archive name longer than 1024 bytes results in an out-of-bounds write that can lead to memory corruption, denial of service, and potentially code execution depending on compiler, build flags, architecture, and memory layout. The overflow occurs prior to any archive parsing or validation.

Read the notes from the security team

Status

Package Ubuntu Release Status
zlib 25.10 questing
Not affected
25.04 plucky
Not affected
24.04 LTS noble
Not affected
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected
rsync 25.10 questing
Not affected
25.04 plucky
Not affected
24.04 LTS noble
Not affected
22.04 LTS jammy
Not affected
20.04 LTS focal
Vulnerable
18.04 LTS bionic
Vulnerable
16.04 LTS xenial
Vulnerable
14.04 LTS trusty
Not affected
klibc 25.10 questing
Needs evaluation
25.04 plucky
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty
Needs evaluation
zsync 25.10 questing
Needs evaluation
25.04 plucky
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation

Notes


mdeslaur

since 3.2.0-1, rsync builds with the system zlib


0xnishit

untgz not presnet since 1:1.2.3.5.dfsg-1 version in zlib