Improper control of a resource through its lifetime in FreeBSD - CVE-2026-45257
Published: June 11, 2026
Vulnerability identifier: #VU134369
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-45257
CWE-ID: CWE-664
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: FreeBSD Foundation
Affected software:
FreeBSD
FreeBSD
Detailed vulnerability description
The vulnerability allows a local user to overwrite arbitrary files and escalate privileges.
The vulnerability exists due to improper handling of file-backed memory in the KTLS receive path when decrypting TLS records received over a loopback connection. A local user can send a readable file over a loopback connection with KTLS receive enabled to overwrite arbitrary files and escalate privileges.
The issue affects software KTLS on the receive path, and the overwrite can modify the page cache directly, bypassing file flags such as schg.
How to mitigate CVE-2026-45257
Install security update from vendor's website.