FreeBSD Security Advisory - Insufficient and improper checking in the NFS server code could cause a denial of service or possibly remote code execution via a specially crafted network packet. A remote attacker could cause the NFS server to crash, resulting in a denial of service, or possibly execute arbitrary code on the server.

FreeBSD Security Advisory - Insufficient bounds checking in one of the device models provided by bhyve(8) can permit a guest operating system to overwrite memory in the bhyve(8) processing possibly permitting arbitrary code execution. A guest OS using a firmware image can cause the bhyve process to crash, or possibly execute arbitrary code on the host as root.

This Metasploit module exploits a vulnerability in the FreeBSD kernel, when running on 64-bit Intel processors. By design, 64-bit processors following the X86-64 specification will trigger a general protection fault (GPF) when executing a SYSRET instruction with a non-canonical address in the RCX register. However, Intel processors check for a non-canonical address prior to dropping privileges, causing a GPF in privileged mode. As a result, the current userland RSP stack pointer is restored and executed, resulting in privileged code execution.

FreeBSD Security Advisory - Multiple vulnerabilities exist in the hostapd(8) and wpa_supplicant(8) implementations.

FreeBSD Security Advisory - On some Intel processors utilizing speculative execution a local process may be able to infer stale information from microarchitectural buffers to obtain a memory disclosure. An attacker may be able to read secret data from the kernel or from a process when executing untrusted code (for example, in a web browser).

This Metasploit module exploits a vulnerability in the FreeBSD run-time link-editor (rtld). The rtld unsetenv() function fails to remove LD_* environment variables if __findenv() fails. This can be abused to load arbitrary shared objects using LD_PRELOAD, resulting in privileged code execution.

Netflix has identified several TCP networking vulnerabilities in FreeBSD and Linux kernels. The vulnerabilities specifically relate to the minimum segment size (MSS) and TCP Selective Acknowledgement (SACK) capabilities. The most serious, dubbed _"SACK Panic_," allows a remotely-triggered kernel panic on recent Linux kernels. There are patches that address most of these vulnerabilities. If patches can not be applied, certain mitigations will be effective.

In the macOS kernel, the XNU function wait_for_namespace_event() in bsd/vfs/vfs_syscalls.c releases a file descriptor for use by userspace but may then subsequently destroy that file descriptor using fp_free(), which unconditionally frees the fileproc and fileglob. This opens up a race window during which the process could manipulate those objects while they're being freed. Exploitation requires root privileges.