Medium [CVE-2023-4806] potential use-after-free in getaddrinfo
This medium-severity Red Hat Linux advisory covers CVE-2023-4806 affecting Red Hat Enterprise Linux 8.6 Extended Update Support, Red Hat Enterprise Linux 9, Red Hat Virtualization 4 for Red Hat Enterprise Linux 8.
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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. This issue is only exploitable with very specific conditions, as detailed in the description.
However, all glibc versions shipped in Red Hat Enterprise Linux are vulnerable to this issue. Red Hat severity: Moderate — CVSS 5.9 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H).
Weakness: CWE-416. Affected Red Hat products: Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 8.6 Extended Update Support; Red Hat Enterprise Linux 9; Red Hat Virtualization 4 for Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7.
Will not fix / out of support: Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7. Red Hat fixing advisory: RHSA-2023:5455, RHSA-2023:7409, RHSA-2023:5453.
Affected products named by the advisory: Red Hat package: glibc; Red Hat package: compat-glibc.
Affected versions
No affected-version range was extracted from the source record. The vendor advisory is authoritative — check it before change work.
Official advisory · high-confidence parse· fetched 9 days ago·verify at source
- glibc-0:2.28-225.el8_8.6
- glibc-0:2.28-189.8.el8_6
- glibc-0:2.34-60.el9_2.7
- RHSA-2023:5455
- RHSA-2023:7409
- RHSA-2023:5453
Official advisory · high-confidence parse· fetched 9 days ago·verify at source
Mitigation
Upgrade to a fixed release: glibc-0:2.28-225.el8_8.6, glibc-0:2.28-189.8.el8_6, glibc-0:2.34-60.el9_2.7, RHSA-2023:5455, RHSA-2023:7409, RHSA-2023:5453. That is the remediation for this advisory.
The vendor advisory may list additional interim mitigations or workarounds not captured here — review it before change work.
Official advisory · high-confidence parse· fetched 9 days ago·verify at source
Discussion(0)
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