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.
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 Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.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 | questing | * |
| Glibc | Ubuntu | trusty | * |
| Glibc | Ubuntu | xenial | * |
Potential Mitigations
References
- https://access.redhat.com/errata/RHBA-2024:2413
- https://access.redhat.com/errata/RHSA-2023:5453
- https://access.redhat.com/errata/RHSA-2023:5455
- https://access.redhat.com/errata/RHSA-2023:7409
- https://access.redhat.com/security/cve/CVE-2023-4806
- https://bugzilla.redhat.com/show_bug.cgi?id=2237782
- 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/errata/RHSA-2023:5453
- https://access.redhat.com/errata/RHSA-2023:5455
- https://access.redhat.com/errata/RHSA-2023:7409
- https://access.redhat.com/security/cve/CVE-2023-4806
- https://bugzilla.redhat.com/show_bug.cgi?id=2237782
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/4DBUQRRPB47TC3NJOUIBVWUGFHBJAFDL/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/DFG4P76UHHZEWQ26FWBXG76N2QLKKPZA/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NDAQWHTSVOCOZ5K6KPIWKRT3JX4RTZUR/
- https://security.gentoo.org/glsa/202310-03
- https://security.netapp.com/advisory/ntap-20240125-0008/