Heap-based buffer overflow in Linux kernel - CVE-2026-89530

Vulnerability identifier: #VU149281

CSH Severity: Medium

CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-89530

CWE-ID: CWE-122

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to corrupt adjacent slab memory.

The vulnerability exists due to a heap-based buffer overflow in svc_rdma_xb_linearize() when processing oversized inline RPC-over-RDMA replies without a Write list or Reply chunk. A remote attacker can request an oversized inline reply without providing a Write list or Reply chunk to corrupt adjacent slab memory.

The posted scatter/gather entry length can cause the device to read beyond the mapped region.

Linux kernel
Debian Linux
Red Hat Enterprise Linux for x86_64
Red Hat CodeReady Linux Builder for ARM 64
Red Hat CodeReady Linux Builder for Power, little endian
Red Hat CodeReady Linux Builder for x86_64
Red Hat Enterprise Linux for ARM 64
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for IBM z Systems
openEuler
Ubuntu
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-gcp (Ubuntu package)
linux-oracle (Ubuntu package)
linux-ibm (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
kernel (Red Hat package)
kernel-tools-debuginfo
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools
kernel-source
kernel-headers
kernel-devel
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
bpftool
kernel
linux (Debian package)

Install security update from vendor's repository.

linux (Ubuntu package) - update to 7.0.0-42.42
linux-aws (Ubuntu package) - update to 7.0.0-1016.17
linux-gcp (Ubuntu package) - update to 7.0.0-1016.18
linux-oracle (Ubuntu package) - update to 7.0.0-1015.16
linux-ibm (Ubuntu package) - update to 7.0.0-1017.17
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-42.42~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1017.17
kernel (Red Hat package) - addressed in versions 4.18.0-553.172.1.el8_10, 6.12.0-211.64.1.el10_2
kernel-tools-debuginfo - update to 5.10.0-339.0.0.240
python3-perf-debuginfo - update to 5.10.0-339.0.0.240
python3-perf - update to 5.10.0-339.0.0.240
perf-debuginfo - update to 5.10.0-339.0.0.240
perf - update to 5.10.0-339.0.0.240
kernel-tools-devel - update to 5.10.0-339.0.0.240
kernel-tools - update to 5.10.0-339.0.0.240
kernel-source - update to 5.10.0-339.0.0.240
kernel-headers - update to 5.10.0-339.0.0.240
kernel-devel - update to 5.10.0-339.0.0.240
kernel-debugsource - update to 5.10.0-339.0.0.240
kernel-debuginfo - update to 5.10.0-339.0.0.240
bpftool-debuginfo - update to 5.10.0-339.0.0.240
bpftool - update to 5.10.0-339.0.0.240
kernel - update to 5.10.0-339.0.0.240
linux (Debian package) - update to 6.12.111-1

• https://git.kernel.org/stable/c/0fbe20dfe74b783d255bf389a6ea77aa25dc7860
• https://git.kernel.org/stable/c/1949dd1576f7a8aa161b1330c6125df9d53046d5
• https://git.kernel.org/stable/c/8ec60eb51fae37cd3d334ff26e4a7d6fb21ff7cf
• https://git.kernel.org/stable/c/fcd91b9957462d398792201c239dffaeff1cc8b2

• Heap-based buffer overflow in Linux kernel sunrpc xprtrdma
• Debian update for linux
• Red Hat Enterprise Linux 8 update for kernel
• Red Hat Enterprise Linux 10 update for kernel
• openEuler 22.03 LTS SP4 update for kernel
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more