Out-of-bounds read in Linux kernel - CVE-2026-43350

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Main Vulnerability Database Vulnerabilities #VU130833

Out-of-bounds read in Linux kernel - CVE-2026-43350

Published: May 9, 2026


Vulnerability identifier: #VU130833
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-43350
CWE-ID: CWE-125
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to disclose sensitive information.

The vulnerability exists due to an out-of-bounds read in parse_dacl() when parsing ACE SIDs returned by an SMB server. A remote attacker can send a specially crafted ACE with a truncated NFS mode SID to disclose sensitive information.

The issue occurs because an ACE with only two subauthorities can still match the NFS mode SID pattern, leading to a read of sid.sub_auth[2] past the end of the ACE.


Affected software

Linux kernel
openEuler
Ubuntu
Anolis OS
kernel-headers
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-source
kernel-devel
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
bpftool
kernel
kernel-extra-modules
kernel-debug
kernel-debug-devel
kernel-tools-libs
kernel-tools-libs-devel
linux (Ubuntu package)
linux-fips (Ubuntu package)
linux-hwe-6.8 (Ubuntu package)
linux-ibm (Ubuntu package)
linux-oracle-6.8 (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-aws-6.8 (Ubuntu package)
linux-aws (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-azure-fde-6.8 (Ubuntu package)
linux-azure (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-gcp-fips (Ubuntu package)
linux-raspi (Ubuntu package)

How to mitigate CVE-2026-43350

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel-headers - addressed in versions 5.10.0-321.0.0.223, 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
python3-perf-debuginfo - addressed in versions 5.10.0-321.0.0.223, 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
python3-perf - addressed in versions 5.10.0-321.0.0.223, 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
perf-debuginfo - addressed in versions 5.10.0-321.0.0.223, 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
perf - addressed in versions 5.10.0-321.0.0.223, 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-tools-devel - addressed in versions 5.10.0-321.0.0.223, 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-tools-debuginfo - addressed in versions 5.10.0-321.0.0.223, 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-tools - addressed in versions 5.10.0-321.0.0.223, 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-source - addressed in versions 5.10.0-321.0.0.223, 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-devel - addressed in versions 5.10.0-321.0.0.223, 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-debugsource - addressed in versions 5.10.0-321.0.0.223, 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-debuginfo - addressed in versions 5.10.0-321.0.0.223, 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
bpftool-debuginfo - addressed in versions 5.10.0-321.0.0.223, 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
bpftool - addressed in versions 5.10.0-321.0.0.223, 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel - addressed in versions 5.10.0-321.0.0.223, 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-extra-modules - update to 6.6.0-145.3.17.150
python3-perf - update to 6.6.102-6
bpftool - update to 6.6.102-6
kernel - update to 6.6.102-6
kernel-debug - update to 6.6.102-6
kernel-debug-devel - update to 6.6.102-6
kernel-devel - update to 6.6.102-6
kernel-headers - update to 6.6.102-6
kernel-tools - update to 6.6.102-6
kernel-tools-libs - update to 6.6.102-6
kernel-tools-libs-devel - update to 6.6.102-6
perf - update to 6.6.102-6
linux (Ubuntu package) - addressed in versions 6.8.0-136.136, 6.8.0-1046.50, 6.8.0-1059.67, 6.8.0-1064.72, 6.8.0-1064.72~22.04.1, 6.8.1-1056.57, 6.8.1-1056.57~22.04.2, 7.0.0-27.27
linux-fips (Ubuntu package) - addressed in versions 6.8.0-136.136+fips2, 6.8.0-136.136.2, 6.8.0-136.136.2~22.04.1, 6.8.0-1058.61
linux-hwe-6.8 (Ubuntu package) - update to 6.8.0-136.136~22.04.1
linux-ibm (Ubuntu package) - addressed in versions 6.8.0-1030.31, 6.8.0-1033.34, 6.8.0-1061.62, 6.8.0-1061.62~22.04.1
linux-oracle-6.8 (Ubuntu package) - update to 6.8.0-1058.61~22.04.1
linux-nvidia (Ubuntu package) - addressed in versions 6.8.0-1059.62, 6.8.0-1059.62.1, 6.8.0-1059.62~22.04.1, 7.0.0-1013.13
linux-aws-6.8 (Ubuntu package) - addressed in versions 6.8.0-1061.64+fips1, 6.8.0-1061.64~22.04.1
linux-aws (Ubuntu package) - update to 6.8.0-1061.64+1
linux-azure-fde (Ubuntu package) - update to 6.8.0-1062.69
linux-azure-fde-6.8 (Ubuntu package) - update to 6.8.0-1062.69~22.04.1
linux-azure (Ubuntu package) - addressed in versions 6.8.0-1063.71, 6.8.0-1063.71~22.04.1, 7.0.0-1009.9, 7.0.0-1010.10
linux-azure-fips (Ubuntu package) - update to 6.8.0-1063.71+fips2
linux-gcp-fips (Ubuntu package) - update to 6.8.0-1064.72+fips1
linux-raspi (Ubuntu package) - update to 7.0.0-1014.14

External References

Related Security Bulletins