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CVE PROGRAM SOURCE RECORD7.8 High

CVE-2026-49429

Kernel heap overflow in ZFS_IOC_USERSPACE_MANY ioctl

Description

The ZFS_IOC_USERSPACE_MANY ioctl, used by zfs-userspace(8), truncated a 64-bit output buffer size to a 32-bit integer for the kernel allocation, but used the original 64-bit size as the buffer limit when writing records. A local user with the "userused" delegated ZFS permission can trigger a kernel heap overflow via the ZFS_IOC_USERSPACE_MANY ioctl, potentially escalating privileges.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

FreeBSD FreeBSD

Default version status: unknown

  • 15.1-RELEASE to < p1affected
  • 15.0-RELEASE to < p11affected
  • 14.4-RELEASE to < p7affected
  • 14.3-RELEASE to < p16affected

References