SB20260928102 - Improper Check for Unusual or Exceptional Conditions in Linux kernel bpf

Description

This security bulletin contains information about 1 vulnerability.

1) Improper Check for Unusual or Exceptional Conditions (CVE-ID: CVE-2026-98085)

CWE-ID: CWE-754 - Improper Check for Unusual or Exceptional Conditions

CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

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

The vulnerability exists due to improper handling of an implicit subprogram exit edge in the BPF verifier's backtrack_insn() function when verifying BPF_LD | BPF_{IND,ABS} instructions. A local user can submit crafted BPF instructions for verification to cause a denial of service.

These instructions are modeled as fallthrough and implicit subprogram exit branches.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/387b1baefbb776e3f48dc2261e77a49213f470f7
• https://git.kernel.org/stable/c/671b7b9a660ef15b25faa3df161205b9dc8d1eb2