Concurrent removals of certain anonymous shared memory mappings by using the UMTXSHMDESTROY sub-request of UMTXOPSHM can lead to decreasing the reference count of the object representing the mapping too many times, causing it to be freed too early.

A malicious code exercizing the UMTXSHMDESTROY sub-request in parallel can panic the kernel or enable further Use-After-Free attacks, potentially including code execution or Capsicum sandbox escape.

A user-provided integer option was passed to nmreqcopyin() without checking if it would overflow. This insufficient bounds checking could lead to kernel memory corruption.

On systems configured to include netmap in their devfsruleset, a privileged process running in a jail can affect the host environment.

Handlers for CFGPAGE read / write ioctls in the mpr, mps, and mpt drivers allocated a buffer of a caller-specified size, but copied to it a fixed size header. Other heap content would be overwritten if the specified size was too small.

Users with access to the mpr, mps or mpt device node may overwrite heap data, potentially resulting in privilege escalation. Note that the device node is only accessible to root and members of the operator group.

In versions of FreeBSD 12.4-RELEASE prior to 12.4-RELEASE-p7 and FreeBSD 13.2-RELEASE prior to 13.2-RELEASE-p5 the sflush() stdio function in libc does not correctly update FILE objects' write space members for write-buffered streams when the write(2) system call returns an error.  Depending on the nature of an application that calls libc's stdio functions and the presence of errors returned from the write(2) system call (or an overridden stdio write routine) a heap buffer overflow may occur. Such overflows may lead to data corruption or the execution of arbitrary code at the privilege level of the calling program.

A malicious value of size in a structure of packed libnv can cause an integer overflow, leading to the allocation of a smaller buffer than required for the parsed data.

The e1000 network adapters permit a variety of modifications to an Ethernet packet when it is being transmitted. These include the insertion of IP and TCP checksums, insertion of an Ethernet VLAN header, and TCP segmentation offload ("TSO"). The e1000 device model uses an on-stack buffer to generate the modified packet header when simulating these modifications on transmitted packets.

When checksum offload is requested for a transmitted packet, the e1000 device model used a guest-provided value to specify the checksum offset in the on-stack buffer. The offset was not validated for certain packet types.

A misbehaving bhyve guest could overwrite memory in the bhyve process on the host, possibly leading to code execution in the host context.

The bhyve process runs in a Capsicum sandbox, which (depending on the FreeBSD version and bhyve configuration) limits the impact of exploiting this issue.

An insufficient boundary validation in the USB code could lead to an out-of-bounds write on the heap, with data controlled by the caller.

A malicious, privileged software running in a guest VM can exploit the vulnerability to achieve code execution on the host in the bhyve userspace process, which typically runs as root. Note that bhyve runs in a Capsicum sandbox, so malicious code is constrained by the capabilities available to the bhyve process.

In FreeBSD 13.0-STABLE before n246938-0729ba2f49c9, 12.2-STABLE before r370383, 11.4-STABLE before r370381, 13.0-RELEASE before p4, 12.2-RELEASE before p10, and 11.4-RELEASE before p13, the ggatec daemon does not validate the size of a response before writing it to a fixed-sized buffer allowing a malicious attacker in a privileged network position to overwrite the stack of ggatec and potentially execute arbitrary code.

The total size of the user-provided nmreq to nmreqcopyin() was first computed and then trusted during the copyin. This time-of-check to time-of-use bug could lead to kernel memory corruption.

On systems configured to include netmap in their devfsruleset, a privileged process running in a jail can affect the host environment.

In FreeBSD 13.0-STABLE before n246941-20f96f215562, 12.2-STABLE before r370400, 11.4-STABLE before r370399, 13.0-RELEASE before p4, 12.2-RELEASE before p10, and 11.4-RELEASE before p13, certain VirtIO-based device models in bhyve failed to handle errors when fetching I/O descriptors. A malicious guest may cause the device model to operate on uninitialized I/O vectors leading to memory corruption, crashing of the bhyve process, and possibly arbitrary code execution in the bhyve process.

In pf packet processing with a 'scrub fragment reassemble' rule, a packet containing multiple IPv6 fragment headers would be reassembled, and then immediately processed. That is, a packet with multiple fragment extension headers would not be recognized as the correct ultimate payload. Instead a packet with multiple IPv6 fragment headers would unexpectedly be interpreted as a fragmented packet, rather than as whatever the real payload is.

As a result, IPv6 fragments may bypass pf firewall rules written on the assumption all fragments have been reassembled and, as a result, be forwarded or processed by the host.

In FreeBSD 13.0-STABLE before n247428-9352de39c3dc, 12.2-STABLE before r370674, 13.0-RELEASE before p6, and 12.2-RELEASE before p12, certain conditions involving use of the highlight buffer while text is scrolling on the console, console data may overwrite data structures associated with the system console or other kernel memory.

In FreeBSD 13.0-STABLE before n245764-876ffe28796c, 12.2-STABLE before r369857, 13.0-RELEASE before p1, and 12.2-RELEASE before p7, a system call triggering a fault could cause SMAP protections to be disabled for the duration of the system call. This weakness could be combined with other kernel bugs to craft an exploit.

In FreeBSD 13.0-STABLE before n245765-bec0d2c9c841, 12.2-STABLE before r369859, 11.4-STABLE before r369866, 13.0-RELEASE before p1, 12.2-RELEASE before p7, and 11.4-RELEASE before p10, missing message validation in libradius(3) could allow malicious clients or servers to trigger denial of service in vulnerable servers or clients respectively.

In versions of FreeBSD 13-RELEASE before 13-RELEASE-p5, under certain circumstances the capnet libcasper(3) service incorrectly validates that updated constraints are strictly subsets of the active constraints.  When only a list of resolvable domain names was specified without setting any other limitations, an application could submit a new list of domains including include entries not previously listed.  This could permit the application to resolve domain names that were previously restricted.

On an msdosfs filesystem, the 'truncate' or 'ftruncate' system calls under certain circumstances populate the additional space in the file with unallocated data from the underlying disk device, rather than zero bytes.

This may permit a user with write access to files on a msdosfs filesystem to read unintended data (e.g. from a previously deleted file).

A particular case of memory sharing is mishandled in the virtual memory system. This is very similar to SA-21:08.vm, but with a different root cause.

An unprivileged local user process can maintain a mapping of a page after it is freed, allowing that process to read private data belonging to other processes or the kernel.

End of life: 8/31/2022