CVE-2026-49427

Summary

Pages belonging to largepage shared memory objects were not explicitly wired. When sendfile(2) transmitted such an object with the SF_NOCACHE flag, it freed the underlying pages after transmission even though existing mappings still referred to them.

An unprivileged local user can abuse the bug to access freed kernel memory. This can be exploited to escalate privileges.

Affected Software

VendorProductVersion RangeStatus
FreeBSDFreeBSD15.1-RELEASE < p1affected
FreeBSDFreeBSD15.0-RELEASE < p11affected
FreeBSDFreeBSD14.4-RELEASE < p7affected
FreeBSDFreeBSD14.3-RELEASE < p16affected

Weaknesses

  • CWE-826: CWE-826: Premature Release of Resource During Expected Lifetime

References