In FreeBSD before 11.1-STABLE, 11.2-RELEASE-p2, 11.1-RELEASE-p13, ip fragment reassembly code is vulnerable to a denial of service due to excessive system resource consumption. This issue can allow a remote attacker who is able to send an arbitrary ip fragments to cause the machine to consume excessive resources.

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.

The routed daemon in FreeBSD 9.3 before 9.3-RELEASE-p22, 10.2-RC2 before 10.2-RC2-p1, 10.2-RC1 before 10.2-RC1-p2, 10.2 before 10.2-BETA2-p3, and 10.1 before 10.1-RELEASE-p17 allows remote authenticated users to cause a denial of service (assertion failure and daemon exit) via a query from a network that is not directly connected.

The sys_amd64 IRET Handler in the kernel in FreeBSD 9.3 and 10.1 allows local users to gain privileges or cause a denial of service (kernel panic).

The inet module in FreeBSD 10.2x before 10.2-PRERELEASE, 10.2-BETA2-p2, 10.2-RC1-p1, 10.1x before 10.1-RELEASE-p16, 9.x before 9.3-STABLE, 9.3-RELEASE-p21, and 8.x before 8.4-STABLE, 8.4-RELEASE-p35 on systems with VNET enabled and at least 16 VNET instances allows remote attackers to cause a denial of service (mbuf consumption) via multiple concurrent TCP connections.

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."

The Linux compatibility layer in the kernel in FreeBSD 9.3, 10.1, and 10.2 allows local users to read portions of kernel memory and potentially gain privilege via unspecified vectors, related to "handling of Linux futex robust lists."

The issetugid system call in the Linux compatibility layer in FreeBSD 9.3, 10.1, and 10.2 allows local users to gain privilege via unspecified vectors.

The kernel in FreeBSD 9.3, 10.1, and 10.2 allows local users to cause a denial of service (crash) or potentially gain privilege via a crafted Linux compatibility layer setgroups system call.

bsnmpd, as used in FreeBSD 9.3, 10.1, and 10.2, uses world-readable permissions on the snmpd.config file, which allows local users to obtain the secret key for USM authentication by reading the file.