In FreeBSD 12.0-STABLE before r350261, 12.0-RELEASE before 12.0-RELEASE-p8, 11.3-STABLE before r350263, 11.3-RELEASE before 11.3-RELEASE-p1, and 11.2-RELEASE before 11.2-RELEASE-p12, system calls operating on file descriptors as part of mqueuefs did not properly release the reference allowing a malicious user to overflow the counter allowing access to files, directories, and sockets opened by processes owned by other users.
In FreeBSD 12.0-STABLE before r350246, 12.0-RELEASE before 12.0-RELEASE-p8, 11.3-STABLE before r350247, 11.3-RELEASE before 11.3-RELEASE-p1, and 11.2-RELEASE before 11.2-RELEASE-p12, the emulated XHCI device included with the bhyve hypervisor did not properly validate data provided by the guest, allowing an out-of-bounds read. This provides a malicious guest the possibility to crash the system or access system memory.
In FreeBSD 11.3-STABLE before r350217, 11.3-RELEASE before 11.3-RELEASE-p1, and 11.2-RELEASE before 11.2-RELEASE-p12, due to insufficient initialization of memory copied to userland in the freebsd32_ioctl interface, small amounts of kernel memory may be disclosed to userland processes. This may allow an attacker to leverage this information to obtain elevated privileges either directly or indirectly.
In FreeBSD 12.0-STABLE before r349805, 12.0-RELEASE before 12.0-RELEASE-p8, 11.3-STABLE before r349806, 11.3-RELEASE before 11.3-RELEASE-p1, and 11.2-RELEASE before 11.2-RELEASE-p12, code which handles close of a descriptor created by posix_openpt fails to undo a signal configuration. This causes an incorrect signal to be raised leading to a write after free of kernel memory allowing a malicious user to gain root privileges or escape a jail.
In FreeBSD 12.0-STABLE before r350222, 12.0-RELEASE before 12.0-RELEASE-p8, 11.3-STABLE before r350223, 11.3-RELEASE before 11.3-RELEASE-p1, and 11.2-RELEASE before 11.2-RELEASE-p12, rights transmitted over a domain socket did not properly release a reference on transmission error allowing a malicious user to cause the reference counter to wrap, forcing a free event. This could allow a malicious local user to gain root privileges or escape from a jail.
The implementations of EAP-PWD in hostapd EAP Server, when built against a crypto library missing explicit validation on imported elements, do not validate the scalar and element values in EAP-pwd-Commit. An attacker may be able to use invalid scalar/element values to complete authentication, gaining session key and network access without needing or learning the password. Both hostapd with SAE support and wpa_supplicant with SAE support prior to and including version 2.4 are affected. Both hostapd with EAP-pwd support and wpa_supplicant with EAP-pwd support prior to and including version 2.7 are affected.
The implementations of EAP-PWD in wpa_supplicant EAP Peer, when built against a crypto library missing explicit validation on imported elements, do not validate the scalar and element values in EAP-pwd-Commit. An attacker may complete authentication, session key and control of the data connection with a client. Both hostapd with SAE support and wpa_supplicant with SAE support prior to and including version 2.4 are affected. Both hostapd with EAP-pwd support and wpa_supplicant with EAP-pwd support prior to and including version 2.7 are affected.
An issue was discovered in OpenSSH 7.9. Due to the scp implementation being derived from 1983 rcp, the server chooses which files/directories are sent to the client. However, the scp client only performs cursory validation of the object name returned (only directory traversal attacks are prevented). A malicious scp server (or Man-in-The-Middle attacker) can overwrite arbitrary files in the scp client target directory. If recursive operation (-r) is performed, the server can manipulate subdirectories as well (for example, to overwrite the .ssh/authorized_keys file).
In FreeBSD before 11.2-STABLE(r341486) and 11.2-RELEASE-p6, insufficient bounds checking in one of the device models provided by bhyve can permit a guest operating system to overwrite memory in the bhyve host 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.
In FreeBSD before 11.2-STABLE(r340854) and 11.2-RELEASE-p5, an integer overflow error when handling opcodes can cause memory corruption by sending a specially crafted NFSv4 request. Unprivileged remote users with access to the NFS server may be able to execute arbitrary code.