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.

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 r356035, 12.1-RELEASE before 12.1-RELEASE-p4, 11.3-STABLE before r356036, and 11.3-RELEASE before 11.3-RELEASE-p8, incomplete packet data validation may result in memory access after it has been freed leading to a kernel panic or other unpredictable results.

In FreeBSD 12.1-STABLE before r356035, 12.1-RELEASE before 12.1-RELEASE-p4, 11.3-STABLE before r356036, and 11.3-RELEASE before 11.3-RELEASE-p8, incomplete packet data validation may result in accessing out-of-bounds memory leading to a kernel panic or other unpredictable results.

In FreeBSD 12.1-STABLE before r357490, 12.1-RELEASE before 12.1-RELEASE-p3, 11.3-STABLE before r357489, and 11.3-RELEASE before 11.3-RELEASE-p7, incorrect use of a user-controlled pointer in the epair virtual network module allowed vnet jailed privileged users to panic the host system and potentially execute arbitrary code in the kernel.

In FreeBSD 12.1-STABLE before r359021, 12.1-RELEASE before 12.1-RELEASE-p3, 11.3-STABLE before r359020, and 11.3-RELEASE before 11.3-RELEASE-p7, a missing null termination check in the jail_set configuration option "osrelease" may return more bytes with a subsequent jail_get system call allowing a malicious jail superuser with permission to create nested jails to read kernel memory.

In FreeBSD 12.1-STABLE before r356606 and 12.1-RELEASE before 12.1-RELEASE-p3, driver specific ioctl command handlers in the ixl network driver failed to check whether the caller has sufficient privileges allowing unprivileged users to trigger updates to the device's non-volatile memory.

In FreeBSD 12.1-STABLE before r358739, 12.1-RELEASE before 12.1-RELEASE-p3, 11.3-STABLE before r358740, and 11.3-RELEASE before 11.3-RELEASE-p7, a TCP SYN-ACK or challenge TCP-ACK segment over IPv6 that is transmitted or retransmitted does not properly initialize the Traffic Class field disclosing one byte of kernel memory over the network.

In FreeBSD 12.1-STABLE before r356089, 12.1-RELEASE before 12.1-RELEASE-p3, 11.3-STABLE before r356090, and 11.3-RELEASE before 11.3-RELEASE-p7, driver specific ioctl command handlers in the oce network driver failed to check whether the caller has sufficient privileges allowing unprivileged users to send passthrough commands to the device firmware.

Server or client applications that call the SSL_check_chain() function during or after a TLS 1.3 handshake may crash due to a NULL pointer dereference as a result of incorrect handling of the "signature_algorithms_cert" TLS extension. The crash occurs if an invalid or unrecognised signature algorithm is received from the peer. This could be exploited by a malicious peer in a Denial of Service attack. OpenSSL version 1.1.1d, 1.1.1e, and 1.1.1f are affected by this issue. This issue did not affect OpenSSL versions prior to 1.1.1d. Fixed in OpenSSL 1.1.1g (Affected 1.1.1d-1.1.1f).