Out-of-bounds write in Linux kernel - CVE-2026-64354
Published: July 27, 2026
Vulnerability identifier: #VU139630
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-64354
CWE-ID: CWE-787
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to an out-of-bounds write in btf_repeat_fields() when processing malformed user-supplied BTF during BPF_BTF_LOAD. A local user can submit crafted BTF data to cause a denial of service.
The issue arises from integer wraparound in the expanded field count calculation before repeated fields are copied into a fixed-size scratch array.
Affected software
Linux kernel
How to mitigate CVE-2026-64354
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3