SB2026072125 - Release of invalid pointer or reference in Linux kernel bpf

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Main Vulnerability Database SB2026072125

SB2026072125 - Release of invalid pointer or reference in Linux kernel bpf

Published: July 21, 2026

Security Bulletin ID SB2026072125
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Denial of service

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Release of invalid pointer or reference (CVE-ID: CVE-2026-63809)

CWE-ID: CWE-763 - Release of invalid pointer or reference

CVSSv4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


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

The vulnerability exists due to memory corruption in proc_sys_call_handler and __cgroup_bpf_run_filter_sysctl() when processing a sysctl write that replaces the temporary buffer. A local privileged user can write a crafted sysctl value to trigger memory corruption and cause a denial of service.

Exploitation requires access to write to a sysctl entry from a task in the target cgroup, and the fault was reproduced while writing to /proc/sys/kernel/domainname.


Remediation

Install update from vendor's website.

References