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 12.2-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 12.2-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 r369346, 11.4-STABLE before r369345, 12.2-RELEASE before p4 and 11.4-RELEASE before p8 a regression in the login.access(5) rule processor has the effect of causing rules to fail to match even when they should not. This means that rules denying access may be ignored.

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 12.1-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 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.

In FreeBSD 12.2-STABLE before r369312, 11.4-STABLE before r369313, 12.2-RELEASE before p4 and 11.4-RELEASE before p8 due to a race condition in the jail_remove(2) implementation, it may fail to kill some of the processes.

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.

The X509_V_FLAG_X509_STRICT flag enables additional security checks of the certificates present in a certificate chain. It is not set by default. Starting from OpenSSL version 1.1.1h a check to disallow certificates in the chain that have explicitly encoded elliptic curve parameters was added as an additional strict check. An error in the implementation of this check meant that the result of a previous check to confirm that certificates in the chain are valid CA certificates was overwritten. This effectively bypasses the check that non-CA certificates must not be able to issue other certificates. If a "purpose" has been configured then there is a subsequent opportunity for checks that the certificate is a valid CA. All of the named "purpose" values implemented in libcrypto perform this check. Therefore, where a purpose is set the certificate chain will still be rejected even when the strict flag has been used. A purpose is set by default in libssl client and server certificate verific…