SB20260928153 - Always-Incorrect Control Flow Implementation in Linux kernel bpf

Description

This security bulletin contains information about 1 vulnerability.

1) Always-Incorrect Control Flow Implementation (CVE-ID: CVE-2026-98048)

CWE-ID: CWE-670 - Always-Incorrect Control Flow Implementation

CVSSv4: 0 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a local user to cause incorrect eBPF program behavior.

The vulnerability exists due to improper control flow handling in the BPF verifier fastcall pattern rewrite logic when processing a spill-call-fill instruction sequence entered by a jump. A local user can load an eBPF program containing such a sequence to cause incorrect eBPF program behavior.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/0b1c83dc3c4401cd7e846548f62e3caf3d06742e
• https://git.kernel.org/stable/c/24adbc2c3bbe3385ce922587e1f8e837a68b3e25