CVE-2026-22184

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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/madler/zlib	Product
https://seclists.org/fulldisclosure/2026/Jan/3	Mailing List Third Party Advisory
https://www.vulncheck.com/advisories/zlib-untgz-global-buffer-overflow-in-tgzfname	Third Party Advisory
https://zlib.net/	Product
https://github.com/madler/zlib/issues/1142	Issue Tracking

Configurations

Configuration 1 (hide)

cpe:2.3:a:zlib:zlib:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-01-07 21:16

Updated : 2026-01-15 14:16

NVD link : CVE-2026-22184

Mitre link : CVE-2026-22184

CVE.ORG link : CVE-2026-22184

JSON object : View

Products Affected

zlib

zlib

CWE

CWE-787

Out-of-bounds Write

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