Out-of-bounds read in Linux kernel - CVE-2026-98611

Vulnerability identifier: #VU156918

CSH Severity: Low

CVSS v4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-98611

CWE-ID: CWE-125

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local privileged user to trigger out-of-bounds kernel memory reads, potentially causing a denial of service.

The vulnerability exists due to an out-of-bounds read in bpf_crypto_ctx_create() in kernel/bpf/crypto.c when processing a parameter buffer shorter than struct bpf_crypto_params. A local privileged user can supply a BPF program that calls the function with a short buffer to cause the kernel to read reserved fields at offsets 14 and 15 beyond the region validated by the verifier, potentially causing a kernel crash.

Linux kernel
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)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
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

• https://git.kernel.org/stable/c/86a0e945fb645ea90233fde239cd2de79f01974c
• https://git.kernel.org/stable/c/a11212910cf09b2fe8db9afa41ef60c4f81879c5
• https://git.kernel.org/stable/c/cd12d3e08620257fbcaa262785d7f4b9473afc7a
• https://git.kernel.org/stable/c/e03253f5d65ebcd2a6d479f140c3bd9c7e4fb84a

• Out-of-bounds read in Linux kernel bpf
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more