In FreeBSD 12.2-STABLE before r369334, 11.4-STABLE before r369335, 12.2-RELEASE before p4 and 11.4-RELEASE before p8 when a process, such as jexec(8) or killall(1), calls jail_attach(2) to enter a jail, the jailed root can attach to it using ptrace(2) before the current working directory is changed.
An OpenSSL TLS server may crash if sent a maliciously crafted renegotiation ClientHello message from a client. If a TLSv1.2 renegotiation ClientHello omits the signature_algorithms extension (where it was present in the initial ClientHello), but includes a signature_algorithms_cert extension then a NULL pointer dereference will result, leading to a crash and a denial of service attack. A server is only vulnerable if it has TLSv1.2 and renegotiation enabled (which is the default configuration). OpenSSL TLS clients are not impacted by this issue. All OpenSSL 1.1.1 versions are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1k. OpenSSL 1.0.2 is not impacted by this issue. Fixed in OpenSSL 1.1.1k (Affected 1.1.1-1.1.1j).
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 verification routines, but it can be overridden or removed by an application. In order to be affected, an application must explicitly set the X509_V_FLAG_X509_STRICT verification flag and either not set a purpose for the certificate verification or, in the case of TLS client or server applications, override the default purpose. OpenSSL versions 1.1.1h and newer are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1k. OpenSSL 1.0.2 is not impacted by this issue. Fixed in OpenSSL 1.1.1k (Affected 1.1.1h-1.1.1j).
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 MidnightBSD before 1.2.6 and 1.3 before August 2020, and FreeBSD before 7, a NULL pointer dereference was found in the Linux emulation layer that allows attackers to crash the running kernel. During binary interaction, td->td_emuldata in sys/compat/linux/linux_emul.h is not getting initialized and returns NULL from em_find().
A memory corruption vulnerability was found in the kernel function kern_getfsstat in MidnightBSD before 1.2.7 and 1.3 through 2020-08-19, and FreeBSD through 11.4, that allows an attacker to trigger an invalid free and crash the system via a crafted size value in conjunction with an invalid mode.
OpenZFS before 2.0.0-rc1, when used on FreeBSD, misinterprets group permissions as user permissions, as demonstrated by mode 0770 being equivalent to mode 0777.
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 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.