CVE-2023-5156: Glibc: dos due to memory leak in getaddrinfo.c

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-09-25 · updated 2026-10-14
Weakness: CWE-401

Description

A flaw was found in the GNU C Library. A recent fix for CVE-2023-4806 introduced the potential for a memory leak, which may result in an application crash.

Affected products

GNU C Library (glibc): from 2.34 before 2.39 — fixed in 2.39
Red Hat Enterprise Linux: 8.0, 9.0

How to fix

Upgrade to a fixed version: GNU C Library (glibc) 2.39. Check the vendor advisory for mitigations.

References

https://access.redhat.com/security/cve/CVE-2023-5156
https://bugzilla.redhat.com/show_bug.cgi?id=2240541
https://sourceware.org/bugzilla/show_bug.cgi?id=30884
https://sourceware.org/git/?p=glibc.git;a=commitdiff;h=ec6b95c3303c700eb89eebeda2d7264cc184a796
http://www.openwall.com/lists/oss-security/2023/10/03/4
http://www.openwall.com/lists/oss-security/2023/10/03/5
http://www.openwall.com/lists/oss-security/2023/10/03/6
http://www.openwall.com/lists/oss-security/2023/10/03/8
https://access.redhat.com/security/cve/CVE-2023-5156
https://bugzilla.redhat.com/show_bug.cgi?id=2240541
https://security.gentoo.org/glsa/202402-01
https://sourceware.org/bugzilla/show_bug.cgi?id=30884

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