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Fencer Vulns
medium 5.9

CVE-2023-4806 json

Glibc: potential use-after-free in getaddrinfo()

published 2023-09-18 3 y ago modified 2026-11-07 46 h ago also EUVD-2023-54650

cvss
5.9
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.6%
EPSS 1.6% chance of exploitation in 30 days, percentile 76%
public exploits
0
none known

Summary

A flaw has been identified 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.

Patch / fix

  • Red Hat Red Hat Enterprise Linux 8 0:2.28-225.el8_8.6
  • Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support 0:2.28-189.8.el8_6
  • Red Hat Red Hat Enterprise Linux 9 0:2.34-60.el9_2.7
  • Red Hat Red Hat Virtualization 4 for Red Hat Enterprise Linux 8 0:2.28-189.8.el8_6
  • glibc Debian 12 2.36-9+deb12u3
  • glibc Debian 14, Debian 13 2.37-10

debian advisories DEBIAN-CVE-2023-4806

  • glibc Ubuntu 20.04 LTS 2.31-0ubuntu9.14
  • glibc Ubuntu 22.04 LTS 2.35-0ubuntu3.5
  • glibc Ubuntu Pro 16.04 LTS 2.23-0ubuntu11.3+esm5
  • glibc Ubuntu Pro 18.04 LTS 2.27-3ubuntu1.6+esm1

ubuntu advisories UBUNTU-CVE-2023-4806

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • glibc RHEL 9 2.34-60.el9_2.7
  • nscd RHEL 9 2.34-60.el9_2.7
  • libnsl RHEL 9 2.34-60.el9_2.7
  • nss_db RHEL 9 2.34-60.el9_2.7
  • nss_hesiod RHEL 9 2.34-60.el9_2.7
  • glibc-utils RHEL 9 2.34-60.el9_2.7
  • glibc-common RHEL 9 2.34-60.el9_2.7
  • glibc-benchtests RHEL 9 2.34-60.el9_2.7

red hat advisories RHSA-2023:7409RHSA-2023:5453RHSA-2023:5455

  • glibc openSUSE Tumbleweed 2.38-3.1

opensuse advisories openSUSE-SU-2024:13273-1

  • glibc AlmaLinux 9 2.34-60.el9_2.7
  • nscd AlmaLinux 9 2.34-60.el9_2.7
  • libnsl AlmaLinux 9 2.34-60.el9_2.7
  • nss_db AlmaLinux 9 2.34-60.el9_2.7
  • nss_hesiod AlmaLinux 9 2.34-60.el9_2.7
  • glibc-utils AlmaLinux 9 2.34-60.el9_2.7
  • glibc-common AlmaLinux 9 2.34-60.el9_2.7
  • glibc-benchtests AlmaLinux 9 2.34-60.el9_2.7

almalinux advisories ALSA-2023:5453ALSA-2023:5455

  • glibc Rocky Linux 8 2.28-225.el8_8.6

rocky linux advisories RLSA-2023:5455

  • glibc CBL-Mariner 2.0 2.35-6
  • glibc Azure Linux 3.0 2.38-11

azure linux advisories AZL-29954AZL-34738

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2023-4806 updated cvss 5.9

glibc: potential use-after-free in getaddrinfo()

  • Red Hat Enterprise Linux 6 nscd, glibc, glibc-utils, compat-glibc, glibc-common
    affected: no fix planned “Out of support scope”
  • Red Hat Enterprise Linux 7 nscd, glibc, glibc-utils, compat-glibc, glibc-common
    affected: no fix planned “Will not fix”
  • Red Hat CodeReady Linux Builder EUS (v.8.6) nss_hesiod 2.28-189.8.el8_6, glibc-benchtests 2.28-189.8.el8_6
    fixed: vendor fix RHSA-2023:7409
  • Red Hat Enterprise Linux AppStream (v. 8) glibc-utils 2.28-225.el8_8.6, compat-libpthread-nonshared 2.28-225.el8_8.6
    fixed: vendor fix RHSA-2023:5455
  • Red Hat Enterprise Linux AppStream (v. 9) glibc-utils 2.34-60.el9_2.7, glibc-locale-source 2.34-60.el9_2.7
    fixed: vendor fix RHSA-2023:5453
  • Red Hat Enterprise Linux AppStream EUS (v.8.6) glibc-utils 2.28-189.8.el8_6, compat-libpthread-nonshared 2.28-189.8.el8_6
    fixed: vendor fix RHSA-2023:7409
  • Red Hat Enterprise Linux BaseOS (v. 8) nscd 2.28-225.el8_8.6, glibc 2.28-225.el8_8.6, libnsl 2.28-225.el8_8.6, nss_db 2.28-225.el8_8.6, glibc-common 2.28-225.el8_8.6, glibc-gconv-extra 2.28-225.el8_8.6, +3 more
    fixed: vendor fix RHSA-2023:5455
  • Red Hat Enterprise Linux BaseOS (v. 9) nscd 2.34-60.el9_2.7, glibc 2.34-60.el9_2.7, libnsl 2.34-60.el9_2.7, glibc-common 2.34-60.el9_2.7, glibc-gconv-extra 2.34-60.el9_2.7, glibc-all-langpacks 2.34-60.el9_2.7, +1 more
    fixed: vendor fix RHSA-2023:5453
show 4 more
  • Red Hat Enterprise Linux BaseOS EUS (v.8.6) nscd 2.28-189.8.el8_6, glibc 2.28-189.8.el8_6, libnsl 2.28-189.8.el8_6, nss_db 2.28-189.8.el8_6, glibc-common 2.28-189.8.el8_6, glibc-gconv-extra 2.28-189.8.el8_6, +3 more
    fixed: vendor fix RHSA-2023:7409
  • Red Hat Enterprise Linux CRB (v. 8) nss_hesiod 2.28-225.el8_8.6, glibc-benchtests 2.28-225.el8_8.6
    fixed: vendor fix RHSA-2023:5455
  • Red Hat Enterprise Linux CRB (v. 9) nss_db 2.34-60.el9_2.7, nss_hesiod 2.34-60.el9_2.7, glibc-benchtests 2.34-60.el9_2.7
    fixed: vendor fix RHSA-2023:5453
  • Red Hat Virtualization 4 Hypervisor for RHEL 8 glibc-devel 2.28-189.8.el8_6, glibc-headers 2.28-189.8.el8_6, nscd-debuginfo 2.28-189.8.el8_6, glibc-debuginfo 2.28-189.8.el8_6, libnsl-debuginfo 2.28-189.8.el8_6, nss_db-debuginfo 2.28-189.8.el8_6, +6 more
    fixed: vendor fix RHSA-2023:7409

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

cisa ICSA-25-162-05 updated cvss 5.9

Siemens SIMATIC S7-1500 CPU family

  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) >= 3.1.5 Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) >= 3.1.5 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) >= 3.1.5 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) >= 3.1.5 Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) >= 3.1.5
    affected: mitigation, no fix available

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

cisa ICSA-23-166-10 updated cvss 5.9

Siemens SIMATIC S7-1500 TM MFP BIOS

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
2 y ago

Exploit prediction

1.61% chance of exploitation in the next 30 days, higher than 76% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

  • Red Hat Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support
  • Red Hat Red Hat Enterprise Linux 9
  • Red Hat Red Hat Virtualization 4 for Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux 6
  • Red Hat Red Hat Enterprise Linux 7
  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP
  • Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP
  • Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.