CVE Vulnerabilities

CVE-2023-4806

Use After Free

Published: Sep 18, 2023 | Modified: Apr 30, 2025
CVSS 3.x
5.9
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS 2.x
RedHat/V2
RedHat/V3
5.9 MODERATE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Ubuntu
LOW

A flaw was found in glibc. In an extremely rare situation, the getaddrinfo function may access memory that has been freed, resulting in an application crash. This issue is only exploitable when a NSS module implements only the nss_gethostbyname2_r and nss_getcanonname_r hooks without implementing the nss*_gethostbyname3_r hook. The resolved name should return a large number of IPv6 and IPv4, and the call to the getaddrinfo function should have the AF_INET6 address family with AI_CANONNAME, AI_ALL and AI_V4MAPPED as flags.

Weakness

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.

Affected Software

Name Vendor Start Version End Version
Glibc Gnu 2.33 (including) 2.33 (including)
Red Hat Enterprise Linux 8 RedHat glibc-0:2.28-225.el8_8.6 *
Red Hat Enterprise Linux 8 RedHat glibc-0:2.28-225.el8_8.6 *
Red Hat Enterprise Linux 8.6 Extended Update Support RedHat glibc-0:2.28-189.8.el8_6 *
Red Hat Enterprise Linux 9 RedHat glibc-0:2.34-100.el9 *
Red Hat Enterprise Linux 9 RedHat glibc-0:2.34-60.el9_2.7 *
Red Hat Enterprise Linux 9 RedHat glibc-0:2.34-100.el9 *
Red Hat Enterprise Linux 9 RedHat glibc-0:2.34-60.el9_2.7 *
Red Hat Virtualization 4 for Red Hat Enterprise Linux 8 RedHat glibc-0:2.28-189.8.el8_6 *
Eglibc Ubuntu trusty *
Eglibc Ubuntu trusty/esm *
Glibc Ubuntu bionic *
Glibc Ubuntu devel *
Glibc Ubuntu esm-infra/bionic *
Glibc Ubuntu esm-infra/focal *
Glibc Ubuntu esm-infra/xenial *
Glibc Ubuntu focal *
Glibc Ubuntu jammy *
Glibc Ubuntu lunar *
Glibc Ubuntu mantic *
Glibc Ubuntu noble *
Glibc Ubuntu oracular *
Glibc Ubuntu plucky *
Glibc Ubuntu trusty *
Glibc Ubuntu xenial *

Potential Mitigations

References