SB20261022211 - Improper input validation in Linux kernel lib bpf
Published: October 22, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Improper input validation (CVE-ID: CVE-2026-98626)
CWE-ID: CWE-20 - Improper input validation
CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N]
The vulnerability allows a local user to bypass relocation-target validation and cause unintended replacement of BPF instructions.
The vulnerability exists due to improper validation of relocation targets before instruction poisoning in bpf_core_patch_insn(), shared by libbpf and in-kernel CO-RE, when processing unresolved CO-RE relocations. A local user can supply malformed relocation metadata targeting instructions that are not eligible for relocation to replace jumps, calls, exits, register-source arithmetic, or non-immediate loads instead of triggering a relocation error.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/2d7d04357c41aa49a5ac658fcc207439f2ad6456
- https://git.kernel.org/stable/c/394ae398337c5f87e567f6cd63b937fc2b2f6ddc
- https://git.kernel.org/stable/c/8e4cbcca1e0a2fc5e6c8edb68e0cf5f2587f9319
- https://git.kernel.org/stable/c/a0b79cdfcf34b53c85bac2d3cf022fc1342eeca0
- https://git.kernel.org/stable/c/a8c47e62d9aea2d47a09e06c1682c59c21b92449
- https://git.kernel.org/stable/c/d3219c229d16900cef936adad28633c98946e432
- https://git.kernel.org/stable/c/f2a24101e89dd0804e717da7c1bd6af513698aa2