SB20261022102 - Incorrect Calculation of Buffer Size in Linux kernel llc

Description

This security bulletin contains information about 1 vulnerability.

1) Incorrect Calculation of Buffer Size (CVE-ID: CVE-2026-98526)

CWE-ID: CWE-131 - Incorrect Calculation of Buffer Size

CVSSv4: 7.1 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker on the local network to potentially cause a denial of service by triggering a kernel socket-buffer headroom underflow.

The vulnerability exists due to insufficient link-layer headroom allocation in llc_alloc_frame() when allocating LLC response frames for stacked Ethernet devices such as VLAN devices. A remote attacker on the local network can send LLC traffic that elicits a response through an affected device to trigger a headroom underflow in eth_header() and potentially cause a denial of service.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/018020f5a48cc86fdd6dc2d380f6c70443ae7639
• https://git.kernel.org/stable/c/16ceac2daa89dd16917bc488ab05b9dd6961a603
• https://git.kernel.org/stable/c/1937222c2511ac91377d39f28106c34734f5f8c6
• https://git.kernel.org/stable/c/3361c93e417384ebf28003e0fb6d5304653d3b05
• https://git.kernel.org/stable/c/3a3f57c4061d9e9cc3bc04205d36ce41ae3406c1
• https://git.kernel.org/stable/c/72b5b9a28b996e09b8b5b944370c79851bb68f52
• https://git.kernel.org/stable/c/7c38524b2b2456bd33cb360420da6cbf9cad1b33
• https://git.kernel.org/stable/c/e06f8b6e27cc616d3c587e9784c4a033eb310a16