Freebsd

In FreeBSD before 11.2-STABLE(r348229), 11.2-RELEASE-p7, 12.0-STABLE(r342228), and 12.0-RELEASE-p1, insufficient validation of network-provided data in bootpd may make it possible for a malicious attacker to craft a bootp packet which could cause a stack buffer overflow. It is possible that the buffer overflow could lead to a Denial of Service or remote code execution.Show less

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.Show less

In FreeBSD before 11.2-STABLE(r340854) and 11.2-RELEASE-p5, the NFS server lacks a bounds check in the READDIRPLUS NFS request. Unprivileged remote users with access to the NFS server can cause a resource exhaustion by forcing the server to allocate an arbitrarily large memory allocation.Show less

In FreeBSD before 11.2-STABLE(r340854) and 11.2-RELEASE-p5, an integer overflow error can occur when handling the client address length field in an NFSv4 request. Unprivileged remote users with access to the NFS server can crash the system by sending a specially crafted NFSv4 request.Show less

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.Show less

In FreeBSD before 11.2-STABLE(r340268) and 11.2-RELEASE-p5, due to incorrectly accounting for padding on 64-bit platforms, a buffer underwrite could occur when constructing an ICMP reply packet when using a non-standard value for the net.inet.icmp.quotelen sysctl.Show less

In FreeBSD before 11.2-STABLE(r338986), 11.2-RELEASE-p4, 11.1-RELEASE-p15, 10.4-STABLE(r338985), and 10.4-RELEASE-p13, due to improper maintenance of IPv6 protocol control block flags through various failure paths, an unprivileged authenticated local user may be able to cause a NULL pointer dereference causing the kernel to crash.Show less

In FreeBSD before 11.2-STABLE(r338983), 11.2-RELEASE-p4, 11.1-RELEASE-p15, 10.4-STABLE(r338984), and 10.4-RELEASE-p13, due to insufficient initialization of memory copied to userland in the getcontext and swapcontext system calls, small amounts of kernel memory may be disclosed to userland processes. Unprivileged authenticated local users may be able to access small amounts privileged kernel data.Show less

In FreeBSD before 11.2-STABLE(r338987), 11.2-RELEASE-p4, and 11.1-RELEASE-p15, due to insufficient memory checking in the freebsd4_getfsstat system call, a NULL pointer dereference can occur. Unprivileged authenticated local users may be able to cause a denial of service.Show less

In FreeBSD before 11.1-STABLE, 11.2-RELEASE-p3, 11.1-RELEASE-p14, 10.4-STABLE, and 10.4-RELEASE-p12, insufficient validation in the ELF header parser could allow a malicious ELF binary to cause a kernel crash or disclose kernel memory.Show less

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.Show less

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.Show less

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.Show less

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.Show less

One of the data structures that holds TCP segments in all versions of FreeBSD prior to 11.2-RELEASE-p1, 11.1-RELEASE-p12, and 10.4-RELEASE-p10 uses an inefficient algorithm to reassemble the data. This causes the CPU time spent on segment processing to grow linearly with the number of segments in the reassembly queue. An attacker who has the ability to send TCP traffic to a victim system can degrade the victim system's network performance and/or consume excessive CPU by exploiting the inefficiency of TCP reassembly handling, with relatively small bandwidth cost.Show less

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.Show less

System software utilizing Lazy FP state restore technique on systems using Intel Core-based microprocessors may potentially allow a local process to infer data from another process through a speculative execution side channel.Show less

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.Show less

In FreeBSD before 11.1-STABLE(r332066) and 11.1-RELEASE-p10, due to insufficient initialization of memory copied to userland in the network subsystem, 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.Show less