Out-of-bounds read in Linux kernel - CVE-2026-63902

 

Out-of-bounds read in Linux kernel - CVE-2026-63902

Published: July 20, 2026


Vulnerability identifier: #VU138755
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-2026-63902
CWE-ID: CWE-125
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

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

The vulnerability exists due to an out-of-bounds read in cypress_read_int_callback() in the cypress_m8 USB serial driver when processing malformed short interrupt packets. A local attacker can provide a specially crafted short interrupt report to cause a denial of service.

Successful interrupt transfers can complete with fewer bytes than required for the selected Cypress packet header format.


Affected software

Linux kernel
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server 12 SP5
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise High Performance Computing 12
SUSE Linux Enterprise Live Patching
Ubuntu
openEuler
kgraft-patch-4_12_14-122_333-default
ocfs2-kmp-default
gfs2-kmp-default
gfs2-kmp-default-debuginfo
kernel-default-devel
ocfs2-kmp-default-debuginfo
cluster-md-kmp-default-debuginfo
kernel-default-base
kernel-syms
kernel-default-base-debuginfo
cluster-md-kmp-default
kernel-default-man
dlm-kmp-default-debuginfo
dlm-kmp-default
kernel-default-debuginfo
kernel-default-kgraft-devel
kernel-default-debugsource
kernel-default-kgraft
kernel-default
kernel-devel
kernel-source
kernel-macros
kernel-default-devel-debuginfo
python3-perf-debuginfo
python3-perf
kernel
bpftool
bpftool-debuginfo
kernel-debuginfo
kernel-debugsource
kernel-headers
kernel-tools
kernel-tools-debuginfo
kernel-tools-devel
perf
perf-debuginfo
linux (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-oracle-5.15 (Ubuntu package)
linux-gcp-5.15 (Ubuntu package)
linux-gcp (Ubuntu package)
linux-gke (Ubuntu package)
linux-azure (Ubuntu package)
linux-ibm (Ubuntu package)
linux-aws (Ubuntu package)
linux-oracle-7.0 (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
linux-nvidia-bos (Ubuntu package)

How to mitigate CVE-2026-63902

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kgraft-patch-4_12_14-122_333-default - update to 1-8.3.3
ocfs2-kmp-default - update to 4.12.14-122.333.2
gfs2-kmp-default - update to 4.12.14-122.333.2
gfs2-kmp-default-debuginfo - update to 4.12.14-122.333.2
kernel-default-devel - update to 4.12.14-122.333.2
ocfs2-kmp-default-debuginfo - update to 4.12.14-122.333.2
cluster-md-kmp-default-debuginfo - update to 4.12.14-122.333.2
kernel-default-base - update to 4.12.14-122.333.2
kernel-syms - update to 4.12.14-122.333.2
kernel-default-base-debuginfo - update to 4.12.14-122.333.2
cluster-md-kmp-default - update to 4.12.14-122.333.2
kernel-default-man - update to 4.12.14-122.333.2
dlm-kmp-default-debuginfo - update to 4.12.14-122.333.2
dlm-kmp-default - update to 4.12.14-122.333.2
kernel-default-debuginfo - update to 4.12.14-122.333.2
kernel-default-kgraft-devel - update to 4.12.14-122.333.2
kernel-default-debugsource - update to 4.12.14-122.333.2
kernel-default-kgraft - update to 4.12.14-122.333.2
kernel-default - update to 4.12.14-122.333.2
kernel-devel - update to 4.12.14-122.333.2
kernel-source - update to 4.12.14-122.333.2
kernel-macros - update to 4.12.14-122.333.2
kernel-default-devel-debuginfo - update to 4.12.14-122.333.2
python3-perf-debuginfo - update to 5.10.0-326.0.0.227
python3-perf - update to 5.10.0-326.0.0.227
kernel - update to 5.10.0-326.0.0.227
bpftool - update to 5.10.0-326.0.0.227
bpftool-debuginfo - update to 5.10.0-326.0.0.227
kernel-debuginfo - update to 5.10.0-326.0.0.227
kernel-debugsource - update to 5.10.0-326.0.0.227
kernel-devel - update to 5.10.0-326.0.0.227
kernel-headers - update to 5.10.0-326.0.0.227
kernel-source - update to 5.10.0-326.0.0.227
kernel-tools - update to 5.10.0-326.0.0.227
kernel-tools-debuginfo - update to 5.10.0-326.0.0.227
kernel-tools-devel - update to 5.10.0-326.0.0.227
perf - update to 5.10.0-326.0.0.227
perf-debuginfo - update to 5.10.0-326.0.0.227
linux (Ubuntu package) - addressed in versions 5.15.0-195.205~20.04.1, 5.15.0-195.205, 5.15.0-198.208~20.04.1, 5.15.0-198.208+fips1, 5.15.0-1080.84, 5.15.0-1100.108, 5.15.0-1109.111, 5.15.0-1109.114, 5.15.0-1111.115~20.04.1, 5.15.0-1111.115, 5.15.0-1112.118~20.04.1, 5.15.0-1112.118, 5.15.0-1113.119, 5.15.0-1114.120, 5.15.0-1116.125~20.04.1, 5.15.0-1117.124~20.04.1, 5.15.0-1117.124, 5.15.0-1117.124+fips1, 5.15.0-1122.131~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1123.132, 5.15.0-1123.132+fips1, 5.15.0.195.160, 5.15.0.195.205~20.04.1, 5.15.0.198.114, 5.15.0.198.171, 5.15.0.198.208~20.04.1, 5.15.0.1080.83~20.04.1, 5.15.0.1100.99, 5.15.0.1109.105, 5.15.0.1109.113, 5.15.0.1111.108, 5.15.0.1111.115~20.04.1, 5.15.0.1112.111, 5.15.0.1112.118~20.04.1, 5.15.0.1113.112, 5.15.0.1114.110, 5.15.0.1116.120, 5.15.0.1117.113, 5.15.0.1117.120, 5.15.0.1117.124~20.04.1, 5.15.0.1122.131~20.04.1, 5.15.0.1123.107, 5.15.0.1123.121, 5.15.0.1123.132~20.04.1
linux-nvidia (Ubuntu package) - addressed in versions 5.15.0-1112.113, 5.15.0.1112.112, 7.0.0-1016.16~24.04.1, 7.0.0-1016.16
linux-oracle-5.15 (Ubuntu package) - addressed in versions 5.15.0-1114.120~20.04.1, 5.15.0.1114.120~20.04.1
linux-gcp-5.15 (Ubuntu package) - addressed in versions 5.15.0-1118.128~20.04.1, 5.15.0.1118.128~20.04.1
linux-gcp (Ubuntu package) - addressed in versions 5.15.0-1118.128, 5.15.0-1118.128+fips1, 5.15.0.1118.107, 5.15.0.1118.115, 6.8.0-1070.78
linux-gke (Ubuntu package) - addressed in versions 6.8.0-146.146.1~22.04.1, 6.8.0-146.146.1, 6.8.0-1051.55, 6.8.0-1063.66, 6.8.0-1064.67~22.04.1, 6.8.0-1064.67, 6.8.0-1064.67.1, 6.8.0-1065.73, 6.8.0-1066.67
linux-azure (Ubuntu package) - addressed in versions 6.8.0-1068.75~22.04.1, 6.8.0-1068.75, 6.8.0-1069.77+fips1, 6.8.0-1070.78~22.04.1, 6.8.0-1070.78, 7.0.0-1009.9, 7.0.0-1010.10
linux-ibm (Ubuntu package) - addressed in versions 7.0.0-1008.8, 7.0.0-1010.10
linux-aws (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1015.15
linux-oracle-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-gcp-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-bos (Ubuntu package) - update to 7.0.0-2016.16

External References

Related Security Bulletins