In FreeBSD 11.x before 11.1-RELEASE and 10.x before 10.4-RELEASE, the qsort algorithm has a deterministic recursion pattern. Feeding a pathological input to the algorithm can lead to excessive stack usage and potential overflow. Applications that use qsort to handle large data set may crash if the input follows the pathological pattern.
In FreeBSD before 11.2-RELEASE, a stack guard-page is available but is disabled by default. This results in the possibility a poorly written process could be cause a stack overflow.
In FreeBSD before 11.2-RELEASE, multiple issues with the implementation of the stack guard-page reduce the protections afforded by the guard-page. This results in the possibility a poorly written process could be cause a stack overflow.
In FreeBSD before 11.2-RELEASE, an application which calls setrlimit() to increase RLIMIT_STACK may turn a read-only memory region below the stack into a read-write region. A specially crafted executable could be exploited to execute arbitrary code in the user context.
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.
An exploitable denial of service vulnerability exists in the origin timestamp check functionality of ntpd 4.2.8p9. A specially crafted unauthenticated network packet can be used to reset the expected origin timestamp for target peers. Legitimate replies from targeted peers will fail the origin timestamp check (TEST2) causing the reply to be dropped and creating a denial of service condition.
In FreeBSD before 11.1-STABLE(r332303), 11.1-RELEASE-p10, 10.4-STABLE(r332321), and 10.4-RELEASE-p9, due to insufficient initialization of memory copied to userland in the Linux subsystem and Atheros wireless driver, small amounts of kernel memory may be disclosed to userland processes. Unprivileged authenticated local users may be able to access small amounts of privileged kernel data.
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-p9, 10.4-STABLE, 10.4-RELEASE-p8 and 10.3-RELEASE-p28, insufficient validation of user-provided font parameters can result in an integer overflow, leading to the use of arbitrary kernel memory as glyph data. Unprivileged users may be able to access privileged kernel data.
In FreeBSD before 11.1-STABLE, 11.1-RELEASE-p9, 10.4-STABLE, 10.4-RELEASE-p8 and 10.3-RELEASE-p28, the length field of the ipsec option header does not count the size of the option header itself, causing an infinite loop when the length is zero. This issue can allow a remote attacker who is able to send an arbitrary packet to cause the machine to crash.