SB2026102201 - Incorrect calculation in Linux kernel bpf

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Main Vulnerability Database SB2026102201

SB2026102201 - Incorrect calculation in Linux kernel bpf

Published: October 22, 2026

Security Bulletin ID SB2026102201
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Code execution

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Incorrect calculation (CVE-ID: CVE-2026-98869)

CWE-ID: CWE-682 - Incorrect Calculation

CVSSv4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a local user to inject arbitrary values into the upper halves of BPF registers, violating the verifier's assumptions about program execution.

The vulnerability exists due to incorrect tracking of register liveness and required zero extension in the Linux kernel BPF verifier when processing 32-bit operations across verification paths that converge at a checkpoint. A local user can submit a specially crafted BPF program to cause required zero extension to be omitted on s390, allowing arbitrary upper-register values to persist where the verifier expects zeros.


Remediation

Install update from vendor's website.

References