Bug 2463465 (CVE-2026-5435)

Summary: CVE-2026-5435 glibc: glibc: Out-of-bounds write via TSIG record processing
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: ashankar, codonell, dj, fweimer, pfrankli, rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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A flaw was found in glibc, the GNU C Library. Specifically, deprecated functions responsible for printing TSIG (Transaction Signature) records fail to properly manage memory buffers. This oversight can lead to an out-of-bounds write when processing specially crafted TSIG records. An attacker could exploit this to cause a denial of service or potentially execute arbitrary code.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-04-28 14:02:07 UTC 
The deprecated functions ns_printrrf, ns_printrr and fp_nquery in the GNU C Library version 2.2 and newer fail to enforce the caller-supplied buffer length, and can result in an out-of-bounds write when printing TSIG records.
Comment 3 errata-xmlrpc 2026-07-21 11:58:17 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:42694 https://access.redhat.com/errata/RHSA-2026:42694
Comment 4 errata-xmlrpc 2026-07-21 14:23:31 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:42733 https://access.redhat.com/errata/RHSA-2026:42733
Comment 5 errata-xmlrpc 2026-07-22 02:46:25 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:42952 https://access.redhat.com/errata/RHSA-2026:42952