Improper bounds checking of the obuf variable in the link_ntoa() function in linkaddr.c of the BSD libc library may allow an attacker to read or write from memory. The full impact and severity depends on the method of exploit and how the library is used by applications. According to analysis by FreeBSD developers, it is very unlikely that applications exist that utilize link_ntoa() in an exploitable manner, and the CERT/CC is not aware of any proof of concept. A blog post describes the functionality of link_ntoa() and points out that none of the base utilities use this function in an exploitable manner. For more information, please see FreeBSD Security Advisory SA-16:37.

In FreeBSD before 11.0-STABLE, 11.0-RELEASE-p10, 10.3-STABLE, and 10.3-RELEASE-p19, ipfilter using "keep state" or "keep frags" options can cause a kernel panic when fed specially crafted packet fragments due to incorrect memory handling.

In FreeBSD before 11.1-STABLE, 11.1-RELEASE-p7, 10.4-STABLE, 10.4-RELEASE-p7, and 10.3-RELEASE-p28, the kernel does not properly validate IPsec packets coming from a trusted host. Additionally, a use-after-free vulnerability exists in the IPsec AH handling code. This issue could cause a system crash or other unpredictable results.

Buffer overflow in the decodearr function in ntpq in ntp 4.2.8p6 through 4.2.8p10 allows remote attackers to execute arbitrary code by leveraging an ntpq query and sending a response with a crafted array.

The telnetd service in FreeBSD 9.3, 10.1, 10.2, 10.3, and 11.0 allows remote attackers to inject arguments to login and bypass authentication via vectors involving a "sequence of memory allocation failures."

Integer overflow in the bhyve hypervisor in FreeBSD 10.1, 10.2, 10.3, and 11.0 when configured with a large amount of guest memory, allows local users to gain privilege via a crafted device descriptor.

The MATCH_ASSOC function in NTP before version 4.2.8p9 and 4.3.x before 4.3.92 allows remote attackers to cause an out-of-bounds reference via an addpeer request with a large hmode value.

Integer overflow in the _gd2GetHeader function in gd_gd2.c in the GD Graphics Library (aka libgd) before 2.2.3, as used in PHP before 5.5.37, 5.6.x before 5.6.23, and 7.x before 7.0.8, allows remote attackers to cause a denial of service (heap-based buffer overflow and application crash) or possibly have unspecified other impact via crafted chunk dimensions in an image.

Integer signedness error in the sockargs function in sys/kern/uipc_syscalls.c in FreeBSD 10.1 before p34, 10.2 before p17, and 10.3 before p3 allows local users to cause a denial of service (memory overwrite and kernel panic) or gain privileges via a negative buflen argument, which triggers a heap-based buffer overflow.

Integer signedness error in the genkbd_commonioctl function in sys/dev/kbd/kbd.c in FreeBSD 9.3 before p42, 10.1 before p34, 10.2 before p17, and 10.3 before p3 allows local users to obtain sensitive information from kernel memory, cause a denial of service (memory overwrite and kernel crash), or gain privileges via a negative value in the flen structure member in the arg argument in a SETFKEY ioctl call, which triggers a "two way heap and stack overflow."