Out-of-bounds read in Linux kernel - CVE-2026-52910

Vulnerability identifier: #VU135030

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-2026-52910

CWE-ID: CWE-125

Exploitation vector: Local access

Exploit availability: No public exploit available

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

The vulnerability exists due to an out-of-bounds read in the reuseport cBPF program handling in sk_reuseport_prog_free() when detaching or replacing a reuseport program while UDP packets are being processed concurrently. A local user can trigger concurrent reuseport program updates and packet transmission to cause a denial of service.

The issue occurs because the classic BPF reuseport program may be freed before RCU readers have completed.

Linux kernel
Debian Linux
openEuler
Ubuntu
kernel
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-headers
kernel-devel
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
bpftool
kernel-source
linux (Debian package)
linux (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel - update to 5.10.0-328.0.0.229
python3-perf-debuginfo - update to 5.10.0-328.0.0.229
python3-perf - update to 5.10.0-328.0.0.229
perf-debuginfo - update to 5.10.0-328.0.0.229
perf - update to 5.10.0-328.0.0.229
kernel-tools-devel - update to 5.10.0-328.0.0.229
kernel-tools-debuginfo - update to 5.10.0-328.0.0.229
kernel-tools - update to 5.10.0-328.0.0.229
kernel-headers - update to 5.10.0-328.0.0.229
kernel-devel - update to 5.10.0-328.0.0.229
kernel-debugsource - update to 5.10.0-328.0.0.229
kernel-debuginfo - update to 5.10.0-328.0.0.229
bpftool-debuginfo - update to 5.10.0-328.0.0.229
bpftool - update to 5.10.0-328.0.0.229
kernel-source - update to 5.10.0-328.0.0.229
linux (Debian package) - update to 6.12.94-1
linux (Ubuntu package) - addressed in versions 7.0.0-31.31, 7.0.0-31.31.1, 7.0.0-31.31~24.04.1, 7.0.0-1006.7, 7.0.0-1011.11~24.04.1, 7.0.0-1012.12, 7.0.0-1012.12~24.04.1
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1013.13

• https://git.kernel.org/stable/c/08264d5bba0bdd3a79bc2984fee09286aba0c4eb
• https://git.kernel.org/stable/c/18fc650ccd7fe3376eca89203668cfb8268f60df
• https://git.kernel.org/stable/c/298db6167f81e9c470a57cf652e4e47757b4293e
• https://git.kernel.org/stable/c/87dfb977bdb6eaa47e9993a34e18f44970f88b1f
• https://git.kernel.org/stable/c/90e47dc5c572d1c73971ac51c7428803f42b78eb
• https://git.kernel.org/stable/c/c3e3fddda6b5d9ba505d218b4055e7d8a282ac57
• https://git.kernel.org/stable/c/f8b8f1d4bb76098e87b8269a0631019648330e6d
• https://git.kernel.org/stable/c/fec41484e7c2aa7ded44c541bba98872be937754

• Out-of-bounds read in Linux kernel core
• Debian update for linux
• openEuler 22.03 LTS SP4 update for kernel
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux
• Ubuntu update for linux-gcp-7.0