Improper Initialization in Linux kernel - CVE-2026-64055

 

Improper Initialization in Linux kernel - CVE-2026-64055

Published: July 20, 2026


Vulnerability identifier: #VU138596
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-64055
CWE-ID: CWE-665
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper state management in the gmac_rx() NAPI poll function when assembling packets from a ring buffer. A local user can trigger processing of fragmented packets across poll cycles to cause a denial of service.

The issue occurs when the ring buffer is completely emptied before a packet has been fully assembled.


Affected software

Linux kernel
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Desktop 15
SUSE Real Time Module
SUSE Linux Enterprise Live Patching
Public Cloud Module
Legacy Module
Development Tools Module
Basesystem Module
Ubuntu
kernel-livepatch-SLE15-SP7-RT_Update_20-debugsource
kernel-livepatch-6_4_0-150700_7_75-rt
kernel-livepatch-6_4_0-150700_7_75-rt-debuginfo
kernel-livepatch-6_4_0-150700_53_81-default
kernel-livepatch-6_4_0-150700_53_81-default-debuginfo
kernel-livepatch-SLE15-SP7_Update_21-debugsource
ocfs2-kmp-rt
gfs2-kmp-rt-debuginfo
dlm-kmp-rt
kernel-rt-devel
kernel-rt-debugsource
kernel-rt-devel-debuginfo
kernel-rt
kernel-devel-rt
kernel-source-rt
cluster-md-kmp-rt-debuginfo
dlm-kmp-rt-debuginfo
gfs2-kmp-rt
kernel-rt-debuginfo
ocfs2-kmp-rt-debuginfo
kernel-syms-rt
cluster-md-kmp-rt
kernel-64kb-debuginfo
gfs2-kmp-default
kernel-64kb
kernel-zfcpdump-debuginfo
kernel-zfcpdump-debugsource
kernel-zfcpdump
kernel-devel
kernel-macros
kernel-default-devel
kernel-default-devel-debuginfo
kernel-default
kernel-default-debugsource
cluster-md-kmp-default-debuginfo
dlm-kmp-default
gfs2-kmp-default-debuginfo
ocfs2-kmp-default
dlm-kmp-default-debuginfo
kernel-default-debuginfo
cluster-md-kmp-default
ocfs2-kmp-default-debuginfo
reiserfs-kmp-default-debuginfo
kernel-default-extra
kernel-default-extra-debuginfo
kernel-azure-devel-debuginfo
kernel-azure-debuginfo
kernel-azure-debugsource
kernel-azure-devel
kernel-azure
kernel-default-livepatch-devel
kernel-default-livepatch
kernel-64kb-devel
reiserfs-kmp-default
kernel-source
kernel-obs-build-debugsource
kernel-obs-build
kernel-syms
kernel-docs
kernel-64kb-debugsource
kernel-64kb-devel-debuginfo
kernel-default-base
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-nvidia-tegra-5.15 (Ubuntu package)
linux-intel-iot-realtime (Ubuntu package)
linux-raspi (Ubuntu package)
linux-intel-iotg (Ubuntu package)
linux-azure-5.15 (Ubuntu package)
linux-azure (Ubuntu package)
linux-gcp-5.15 (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-lowlatency (Ubuntu package)
linux-gcp-6.8 (Ubuntu package)
linux-oracle (Ubuntu package)
linux-aws-fips (Ubuntu package)
linux-azure-6.8 (Ubuntu package)
linux-raspi-realtime (Ubuntu package)
linux-ibm (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oracle-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-nvidia-bos (Ubuntu package)

How to mitigate CVE-2026-64055

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel-livepatch-SLE15-SP7-RT_Update_20-debugsource - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_75-rt - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_75-rt-debuginfo - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_53_81-default - update to 1-150700.15.3.1
kernel-livepatch-6_4_0-150700_53_81-default-debuginfo - update to 1-150700.15.3.1
kernel-livepatch-SLE15-SP7_Update_21-debugsource - update to 1-150700.15.3.1
ocfs2-kmp-rt - update to 6.4.0-150700.7.75.1
gfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.75.1
dlm-kmp-rt - update to 6.4.0-150700.7.75.1
kernel-rt-devel - update to 6.4.0-150700.7.75.1
kernel-rt-debugsource - update to 6.4.0-150700.7.75.1
kernel-rt-devel-debuginfo - update to 6.4.0-150700.7.75.1
kernel-rt - update to 6.4.0-150700.7.75.1
kernel-devel-rt - update to 6.4.0-150700.7.75.1
kernel-source-rt - update to 6.4.0-150700.7.75.1
cluster-md-kmp-rt-debuginfo - update to 6.4.0-150700.7.75.1
dlm-kmp-rt-debuginfo - update to 6.4.0-150700.7.75.1
gfs2-kmp-rt - update to 6.4.0-150700.7.75.1
kernel-rt-debuginfo - update to 6.4.0-150700.7.75.1
ocfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.75.1
kernel-syms-rt - update to 6.4.0-150700.7.75.1
cluster-md-kmp-rt - update to 6.4.0-150700.7.75.1
kernel-64kb-debuginfo - update to 6.4.0-150700.53.81.1
gfs2-kmp-default - update to 6.4.0-150700.53.81.1
kernel-64kb - update to 6.4.0-150700.53.81.1
kernel-zfcpdump-debuginfo - update to 6.4.0-150700.53.81.1
kernel-zfcpdump-debugsource - update to 6.4.0-150700.53.81.1
kernel-zfcpdump - update to 6.4.0-150700.53.81.1
kernel-devel - update to 6.4.0-150700.53.81.1
kernel-macros - update to 6.4.0-150700.53.81.1
kernel-default-devel - update to 6.4.0-150700.53.81.1
kernel-default-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-default - update to 6.4.0-150700.53.81.1
kernel-default-debugsource - update to 6.4.0-150700.53.81.1
cluster-md-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
dlm-kmp-default - update to 6.4.0-150700.53.81.1
gfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
ocfs2-kmp-default - update to 6.4.0-150700.53.81.1
dlm-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
kernel-default-debuginfo - update to 6.4.0-150700.53.81.1
cluster-md-kmp-default - update to 6.4.0-150700.53.81.1
ocfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
kernel-default-extra - update to 6.4.0-150700.53.81.1
kernel-default-extra-debuginfo - update to 6.4.0-150700.53.81.1
kernel-azure-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-azure-debuginfo - update to 6.4.0-150700.53.81.1
kernel-azure-debugsource - update to 6.4.0-150700.53.81.1
kernel-azure-devel - update to 6.4.0-150700.53.81.1
kernel-azure - update to 6.4.0-150700.53.81.1
kernel-default-livepatch-devel - update to 6.4.0-150700.53.81.1
kernel-default-livepatch - update to 6.4.0-150700.53.81.1
kernel-64kb-devel - update to 6.4.0-150700.53.81.1
reiserfs-kmp-default - update to 6.4.0-150700.53.81.1
kernel-source - update to 6.4.0-150700.53.81.1
kernel-obs-build-debugsource - update to 6.4.0-150700.53.81.1
kernel-obs-build - update to 6.4.0-150700.53.81.1
kernel-syms - update to 6.4.0-150700.53.81.1
kernel-docs - update to 6.4.0-150700.53.81.1
kernel-64kb-debugsource - update to 6.4.0-150700.53.81.1
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-default-base - update to 6.4.0-150700.53.81.1.150700.17.45.1
linux (Ubuntu package) - addressed in versions 5.15.0-184.194~20.04.1, 5.15.0-184.194, 5.15.0-186.196~20.04.1, 5.15.0-186.196, 5.15.0-1075.79, 5.15.0-1095.103, 5.15.0-1104.109, 5.15.0-1108.114, 5.15.0-1111.120+fips1, 5.15.0-1112.122, 5.15.0-1112.122+fips1, 5.15.0.184.155, 5.15.0.186.166, 5.15.0.1075.78, 5.15.0.1095.94, 5.15.0.1104.100, 5.15.0.1108.107, 5.15.0.1111.115, 5.15.0.1112.102, 5.15.0.1112.109, 6.8.0-139.139+fips1, 6.8.0-1049.53, 6.8.0-1062.65~22.04.1, 6.8.0-1062.65+fips1, 6.8.0-1062.65.1, 6.8.0-1062.70, 6.8.0-1064.68, 6.8.0-1067.75, 6.8.0-1067.75+fips1, 6.8.1-1059.60~22.04.1, 6.8.1-1059.60
linux-aws (Ubuntu package) - addressed in versions 5.15.0-186.196+fips1, 5.15.0-1106.110, 5.15.0-1107.108, 5.15.0-1112.119~20.04.1, 5.15.0-1112.119, 5.15.0-1112.119+fips1, 5.15.0.186.109, 5.15.0.1106.103, 5.15.0.1107.107, 5.15.0.1112.108, 5.15.0.1112.115, 6.8.0-1064.67~22.04.1, 7.0.0-1009.9, 7.0.0-1015.15
linux-nvidia-tegra (Ubuntu package) - addressed in versions 5.15.0-1053.53, 5.15.0-1064.66, 5.15.0.1053.55, 5.15.0.1064.64, 6.8.0-1035.38
linux-nvidia-tegra-5.15 (Ubuntu package) - update to 5.15.0-1064.66~20.04.1
linux-intel-iot-realtime (Ubuntu package) - addressed in versions 5.15.0-1104.106, 5.15.0-1107.113~20.04.1, 5.15.0.1104.108
linux-raspi (Ubuntu package) - addressed in versions 5.15.0-1106.109, 5.15.0.1106.104
linux-intel-iotg (Ubuntu package) - addressed in versions 5.15.0-1107.113, 5.15.0.1107.106
linux-azure-5.15 (Ubuntu package) - addressed in versions 5.15.0-1109.115~20.04.1, 5.15.0-1117.126~20.04.1, 5.15.0-1117.126~20.04.2
linux-azure (Ubuntu package) - addressed in versions 5.15.0-1109.115, 5.15.0-1117.126, 5.15.0.1109.105, 5.15.0.1117.115, 6.8.0-1067.75, 7.0.0-1009.9, 7.0.0-1010.10
linux-gcp-5.15 (Ubuntu package) - update to 5.15.0-1112.122~20.04.1
linux-azure-fde (Ubuntu package) - update to 5.15.0-1117.126
linux-azure-fips (Ubuntu package) - addressed in versions 5.15.0-1117.126+fips1, 5.15.0.1117.102, 6.8.0-1067.75+fips1
linux-lowlatency (Ubuntu package) - addressed in versions 6.8.0-139.139.1~22.04.1, 6.8.0-139.139.1
linux-gcp-6.8 (Ubuntu package) - addressed in versions 6.8.0-1036.37, 6.8.0-1064.65, 6.8.0-1067.75~22.04.1
linux-oracle (Ubuntu package) - addressed in versions 6.8.0-1061.64~22.04.1, 6.8.0-1061.64
linux-aws-fips (Ubuntu package) - update to 6.8.0-1064.67+fips1
linux-azure-6.8 (Ubuntu package) - update to 6.8.0-1067.75~22.04.1
linux-raspi-realtime (Ubuntu package) - update to 6.8.0-2053.55
linux-ibm (Ubuntu package) - addressed in versions 7.0.0-1008.8, 7.0.0-1010.10
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-oracle-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-azure-7.0 (Ubuntu package) - update to 7.0.0-1014.14~24.04.1
linux-nvidia (Ubuntu package) - addressed in versions 7.0.0-1016.16~24.04.1, 7.0.0-1016.16
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2016.16

External References

Related Security Bulletins