Out-of-bounds read in Linux kernel - CVE-2026-64450

Vulnerability identifier: #VU139498

CSH Severity: Medium

CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-64450

CWE-ID: CWE-125

Exploitation vector: Remote access

Exploit availability: No public exploit available

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

The vulnerability exists due to an out-of-bounds read in the TIPC broadcast Gap ACK blocks handling in tipc_bcast_sync_rcv() when processing a crafted broadcast PROTOCOL/STATE_MSG. A remote attacker can send a specially crafted broadcast STATE_MSG with a malformed Gap ACK blocks record to cause a denial of service.

Exploitation requires a TIPC neighbour that has negotiated TIPC_GAP_ACK_BLOCK.

Linux kernel
openEuler
Ubuntu
bpftool
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
kernel
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
bpftool - 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
kernel - update to 5.10.0-331.0.0.232
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/016f5995c37a5a2c45198308f830f244517d70b7
• https://git.kernel.org/stable/c/055663d21dc4336f67933ab26bef3c5934be6324
• https://git.kernel.org/stable/c/2b66974a1b6134a4bbc3bfed181f7418f688eb54
• https://git.kernel.org/stable/c/2de42e268174766cb2e2b90721afdfdff70e0d8d
• https://git.kernel.org/stable/c/74b45af86a767594ba52330cd440ea84e24d700d
• https://git.kernel.org/stable/c/9a51115fcdc78687c8852bf93a1db3951dbb223b
• https://git.kernel.org/stable/c/a21ed5064217cc33726da6c7ef1a520eba43aea1
• https://git.kernel.org/stable/c/f333b6851bdf326fd2134133272dbbed0c94d921

• Out-of-bounds read in Linux kernel tipc
• 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