Out-of-bounds read in Linux kernel - CVE-2026-80557

Vulnerability identifier: #VU145931

CSH Severity: High

CVSS v4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-80557

CWE-ID: CWE-125

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to disclose sensitive information, execute arbitrary code, or cause a denial of service.

The vulnerability exists due to an out-of-bounds read in decode_watchers() when processing a crafted obj_list_watch_response_t reply with struct_len set to 0. A remote attacker can send a specially crafted OSD response to disclose sensitive information, execute arbitrary code, or cause a denial of service.

Exploitation requires a malicious or compromised OSD and can be triggered when a kernel client invokes CEPH_OSD_OP_LIST_WATCHERS.

Linux kernel
Debian Linux
openEuler
Ubuntu
kernel
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-source
kernel-headers
kernel-devel
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
bpftool
linux-nvidia-tegra (Ubuntu package)
linux (Debian package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel - update to 5.10.0-331.0.0.232
python3-perf-debuginfo - update to 5.10.0-331.0.0.232
python3-perf - update to 5.10.0-331.0.0.232
perf-debuginfo - update to 5.10.0-331.0.0.232
perf - update to 5.10.0-331.0.0.232
kernel-tools-devel - update to 5.10.0-331.0.0.232
kernel-tools-debuginfo - update to 5.10.0-331.0.0.232
kernel-tools - update to 5.10.0-331.0.0.232
kernel-source - update to 5.10.0-331.0.0.232
kernel-headers - update to 5.10.0-331.0.0.232
kernel-devel - update to 5.10.0-331.0.0.232
kernel-debugsource - update to 5.10.0-331.0.0.232
kernel-debuginfo - update to 5.10.0-331.0.0.232
bpftool-debuginfo - update to 5.10.0-331.0.0.232
bpftool - update to 5.10.0-331.0.0.232
linux-nvidia-tegra (Ubuntu package) - update to 6.8.0-1036.39+1
linux (Debian package) - update to 6.12.107-1

• https://git.kernel.org/stable/c/00ead17c7de137a692edee59f2772e6af687e8eb
• https://git.kernel.org/stable/c/7130d94846dadbb97b6b7f4d78a3a7bba6e3daa1

• Out-of-bounds read in Linux kernel ceph
• Debian update for linux
• openEuler 22.03 LTS SP4 update for kernel
• Ubuntu update for linux-nvidia-tegra