In FreeBSD 12.2-STABLE before r367402, 11.4-STABLE before r368202, 12.2-RELEASE before p1, 12.1-RELEASE before p11 and 11.4-RELEASE before p5 the handler for a routing option caches a pointer into the packet buffer holding the ICMPv6 message. However, when processing subsequent options the packet buffer may be freed, rendering the cached pointer invalid. The network stack may later dereference the pointer, potentially triggering a use-after-free.

In FreeBSD 12.2-STABLE before r368250, 11.4-STABLE before r368253, 12.2-RELEASE before p1, 12.1-RELEASE before p11 and 11.4-RELEASE before p5 when processing a DNSSL option, rtsold(8) decodes domain name labels per an encoding specified in RFC 1035 in which the first octet of each label contains the label's length. rtsold(8) did not validate label lengths correctly and could overflow the destination buffer.

In FreeBSD 12.2-STABLE before r368250, 11.4-STABLE before r368253, 12.2-RELEASE before p1, 12.1-RELEASE before p11 and 11.4-RELEASE before p5 rtsold(8) does not verify that the RDNSS option does not extend past the end of the received packet before processing its contents. While the kernel currently ignores such malformed packets, it passes them to userspace programs. Any programs expecting the kernel to do validation may be vulnerable to an overflow.

In FreeBSD 12.2-STABLE before r365772, 11.4-STABLE before r365773, 12.1-RELEASE before p10, 11.4-RELEASE before p4 and 11.3-RELEASE before p14 a ftpd(8) bug in the implementation of the file system sandbox, combined with capabilities available to an authenticated FTP user, can be used to escape the file system restriction configured in ftpchroot(5). Moreover, the bug allows a malicious client to gain root privileges.

In FreeBSD 12.2-STABLE before r365767, 11.4-STABLE before r365769, 12.1-RELEASE before p10, 11.4-RELEASE before p4 and 11.3-RELEASE before p14 a number of AMD virtualization instructions operate on host physical addresses, are not subject to nested page table translation, and guest use of these instructions was not trapped.

In FreeBSD 12.2-STABLE before r365730, 11.4-STABLE before r365738, 12.1-RELEASE before p10, 11.4-RELEASE before p4, and 11.3-RELEASE before p14, a programming error in the ure(4) device driver caused some Realtek USB Ethernet interfaces to incorrectly report packets with more than 2048 bytes in a single USB transfer as having a length of only 2048 bytes. An adversary can exploit this to cause the driver to misinterpret part of the payload of a large packet as a separate packet, and thereby inject packets across security boundaries such as VLANs.

In FreeBSD 12.1-STABLE before r364644, 11.4-STABLE before r364651, 12.1-RELEASE before p9, 11.4-RELEASE before p3, and 11.3-RELEASE before p13, improper handling in the kernel causes a use-after-free bug by sending large user messages from multiple threads on the same SCTP socket. The use-after-free situation may result in unintended kernel behaviour including a kernel panic.

In FreeBSD 12.1-STABLE before r365010, 11.4-STABLE before r365011, 12.1-RELEASE before p9, 11.4-RELEASE before p3, and 11.3-RELEASE before p13, dhclient(8) fails to handle certain malformed input related to handling of DHCP option 119 resulting a heap overflow. The heap overflow could in principle be exploited to achieve remote code execution. The affected process runs with reduced privileges in a Capsicum sandbox, limiting the immediate impact of an exploit.

In FreeBSD 12.2-STABLE before r368969, 11.4-STABLE before r369047, 12.2-RELEASE before p3, 12.1-RELEASE before p13 and 11.4-RELEASE before p7 msdosfs(5) was failing to zero-fill a pair of padding fields in the dirent structure, resulting in a leak of three uninitialized bytes.

In FreeBSD 12.2-STABLE before r368969, 11.4-STABLE before r369047, 12.2-RELEASE before p3, 12.1-RELEASE before p13 and 11.4-RELEASE before p7 several file systems were not properly initializing the d_off field of the dirent structures returned by VOP_READDIR. In particular, tmpfs(5), smbfs(5), autofs(5) and mqueuefs(5) were failing to do so. As a result, eight uninitialized kernel stack bytes may be leaked to userspace by these file systems.

bhyve, as used in FreeBSD through 12.1 and illumos (e.g., OmniOS CE through r151034 and OpenIndiana through Hipster 2020.04), does not properly restrict VMCS and VMCB read/write operations, as demonstrated by a root user in a container on an Intel system, who can gain privileges by modifying VMCS_HOST_RIP.

In FreeBSD 12.1-STABLE before r363918, 12.1-RELEASE before p8, 11.4-STABLE before r363919, 11.4-RELEASE before p2, and 11.3-RELEASE before p12, the sendmsg system call in the compat32 subsystem on 64-bit platforms has a time-of-check to time-of-use vulnerability allowing a mailcious userspace program to modify control message headers after they were validation.

In FreeBSD 12.1-STABLE before r362166, 12.1-RELEASE before p8, 11.4-STABLE before r362167, 11.4-RELEASE before p2, and 11.3-RELEASE before p12, missing length validation code common to mulitple USB network drivers allows a malicious USB device to write beyond the end of an allocated network packet buffer.

In FreeBSD 12.1-STABLE before r359565, 12.1-RELEASE before p7, 11.4-STABLE before r362975, 11.4-RELEASE before p1, and 11.3-RELEASE before p11, missing synchronization in the IPV6_2292PKTOPTIONS socket option set handler contained a race condition allowing a malicious application to modify memory after being freed, possibly resulting in code execution.

In FreeBSD 12.1-STABLE before r361918, 12.1-RELEASE before p6, 11.4-STABLE before r361919, 11.3-RELEASE before p10, and 11.4-RC2 before p1, an invalid memory location may be used for HID items if the push/pop level is not restored within the processing of that HID item allowing an attacker with physical access to a USB port to be able to use a specially crafted USB device to gain kernel or user-space code execution.

SQLite through 3.32.0 has an integer overflow in sqlite3_str_vappendf in printf.c.

In FreeBSD 12.1-STABLE before r360973, 12.1-RELEASE before p5, 11.4-STABLE before r360973, 11.4-BETA1 before p1 and 11.3-RELEASE before p9, the FTP packet handler in libalias incorrectly calculates some packet length allowing disclosure of small amounts of kernel (for kernel NAT) or natd process space (for userspace natd).

In FreeBSD 12.1-STABLE before r360971, 12.1-RELEASE before p5, 11.4-STABLE before r360971, 11.4-BETA1 before p1 and 11.3-RELEASE before p9, libalias does not properly validate packet length resulting in modules causing an out of bounds read/write condition if no checking was built into the module.

In FreeBSD 12.1-STABLE before r356911, and 12.1-RELEASE before p5, insufficient checking in the cryptodev module allocated the size of a kernel buffer based on a user-supplied length allowing an unprivileged process to trigger a kernel panic.

In FreeBSD 12.1-STABLE before r356908, 12.1-RELEASE before p5, 11.3-STABLE before r356908, and 11.3-RELEASE before p9, a race condition in the cryptodev module permitted a data structure in the kernel to be used after it was freed, allowing an unprivileged process can overwrite arbitrary kernel memory.