Description
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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| 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 | — | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | glibc | 2.37-10 | — |
| Debian 13 | glibc | 2.37-10 | — |
| Debian 12 | glibc | 2.36-9+deb12u3 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | glibc | 2.35-0ubuntu3.5 | USN-6541-1 |
| Ubuntu 20.04 LTS | glibc | 2.31-0ubuntu9.14 | USN-6541-1 |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | glibc | 2.27-3ubuntu1.6+esm1 | USN-6541-1 |
| Ubuntu Pro 16.04 LTS | glibc | 2.23-0ubuntu11.3+esm5 | USN-6541-1 |
| Ubuntu Pro 14.04 LTS | eglibc | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9 | nscd +214 | 2.34-60.el9_2.7 | RHSA-2023:5453 |
| RHEL 8 | nscd +213 | 2.28-225.el8_8.6 | RHSA-2023:5455 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Rhev Hypervisor 4 | glibc-devel +1 | 2.28-189.8.el8_6 | RHSA-2023:7409 |
| RHEL 8.6 EUS | nscd +213 | 2.28-189.8.el8_6 | RHSA-2023:7409 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 9 | nscd +214 | 2.34-60.el9_2.7 | ALSA-2023:5453 |
| AlmaLinux 8 | nscd +213 | 2.28-225.el8_8.6 | ALSA-2023:5455 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | glibc | 2.28-225.el8_8.6 | RLSA-2023:5455 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | glibc | 2.38-3.1 | openSUSE-SU-2024:13273-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | nscd +217 | 2.34-52.amzn2023.0.6 | ALAS2023-2023-359 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | glibc | 2.38-11 | — |
| Azure Linux 2 (CBL-Mariner) | glibc | 2.35-6 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | nscd +214 | 2.34-60.0.3.el9_2.7 | ELSA-2023-5453 |
| Oracle Linux 8 | nscd +213 | 2.28-225.0.4.el8_8.6 | ELSA-2023-5455 |
Advisories 17
- ALSA-2023:5453 Important: glibc security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2023:5455 Important: glibc security update AlmaLinux Security Advisories · Oct 29, 2026
- SSA-082556 SSA-082556: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1.5 Siemens ProductCERT · Oct 13, 2026
- WID-SEC-2023-2384 GNU libc: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 1, 2026
- RHSA-2023:7409 Red Hat Security Advisory: glibc security update Red Hat Security Advisories (RHSA) · Jul 15, 2026
- RHSA-2023:5455 Red Hat Security Advisory: glibc security update Red Hat Security Advisories (RHSA) · Jul 15, 2026
- RHSA-2023:5453 Red Hat Security Advisory: glibc security update Red Hat Security Advisories (RHSA) · Jul 15, 2026
- USN-6541-1 glibc vulnerabilities Ubuntu Security Notices (USN) · Jun 25, 2026
- ICSA-25-162-05 Siemens SIMATIC S7-1500 CPU family CISA ICS & IT advisories · May 14, 2026
- RLSA-2023:5455 Important: glibc security update Rocky Linux Security Advisories · Feb 5, 2026
- openSUSE-SU-2024:13273-1 glibc-2.38-3.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- NCSC-2025-0187 Kwetsbaarheden verholpen in Siemens producten NCSC-NL (Netherlands) · Jun 10, 2025
- ICSA-23-166-10 Siemens SIMATIC S7-1500 TM MFP BIOS CISA ICS & IT advisories · Apr 9, 2024
- SSA-831302 SSA-831302: Vulnerabilities in the BIOS of the SIMATIC S7-1500 TM MFP before V1.3.0 Siemens ProductCERT · Apr 9, 2024
- ELSA-2023-5455 Important: glibc security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Dec 19, 2023
- ELSA-2023-5453 Important: glibc security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Oct 10, 2023
- ALAS2023-2023-359 Important: glibc security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Oct 3, 2023
References
- RHSA-2023:5453 vendor-advisory
- RHSA-2023:5455 vendor-advisory
- RHSA-2023:7409 vendor-advisory
- https://access.redhat.com/security/cve/CVE-2023-4806 vdb-entry
- RHBZ#2237782 issue-tracking