SB20261007130 - Improper initialization in Linux kernel ipv4

Description

This security bulletin contains information about 1 vulnerability.

1) Improper initialization (CVE-ID: CVE-2026-98240)

CWE-ID: CWE-665 - Improper Initialization

CVSSv4: 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]

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

The vulnerability exists due to improper initialization of the options_len counter in net/ipv4/ip_tunnel_core.c when parsing IP tunnel options during route configuration. A local user can configure an IP route with Geneve options to trigger a kernel panic and cause a denial of service.

The demonstrated panic occurs on kernels built with GCC 15 or later and CONFIG_FORTIFY_SOURCE enabled. The fortified memcpy detects a four-byte write to a destination whose reported size is zero.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/0f6a6beb01c068fcd5274eabf22c260039749fea
• https://git.kernel.org/stable/c/455ebeadf714f51e1dbbd6a022c74c9215b1cd76
• https://git.kernel.org/stable/c/9907325257b4b382f26aafd5d9a8d47915907dd5