| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| The 4BSD process scheduler in the FreeBSD kernel performs scheduling based on CPU billing gathered from periodic process sampling ticks, which allows local users to cause a denial of service (CPU consumption) by performing voluntary nanosecond sleeps that result in the process not being active during a clock interrupt, as described in "Secretly Monopolizing the CPU Without Superuser Privileges." |
| Each RPCSEC_GSS data packet is validated by a routine which checks a signature in the packet. This routine copies a portion of the packet into a stack buffer, but fails to ensure that the buffer is sufficiently large, and a malicious client can trigger a stack overflow. Notably, this does not require the client to authenticate itself first.
As kgssapi.ko's RPCSEC_GSS implementation is vulnerable, remote code execution in the kernel is possible by an authenticated user that is able to send packets to the kernel's NFS server while kgssapi.ko is loaded into the kernel.
In userspace, applications which have librpcgss_sec loaded and run an RPC server are vulnerable to remote code execution from any client able to send it packets. We are not aware of any such applications in the FreeBSD base system. |
| The rtsock_msg_buffer() function serializes routing information into a buffer. As a part of this, it copies sockaddr structures into a sockaddr_storage structure on the stack. It assumes that the source sockaddr length field had already been validated, but this is not necessarily the case, and it's possible for a malicious userspace program to craft a request which triggers a 127-byte overflow.
In practice, this overflow immediately overwrites the canary for the rtsock_msg_buffer() stack frame, resulting in a panic once the function returns.
The bug allows an unprivileged user to crash the kernel by triggering a stack buffer overflow in rtsock_msg_buffer(). In particular, the overflow will corrupt a stack canary value that is verified when the function returns; this mitigates the impact of the stack overflow by triggering a kernel panic.
Other kernel bugs may exist which allow userspace to find the canary value and thus defeat the mitigation, at which point local privilege escalation may be possible. |
| Due to a programming error, blocklistd leaks a socket descriptor for each adverse event report it receives.
Once a certain number of leaked sockets is reached, blocklistd becomes unable to run the helper script: a child process is forked, but this child dereferences a null pointer and crashes before it is able to exec the helper. At this point, blocklistd still records adverse events but is unable to block new addresses or unblock addresses whose database entries have expired.
Once a second, much higher number of leaked sockets is reached, blocklistd becomes unable to receive new adverse event reports.
An attacker may take advantage of this by triggering a large number of adverse events from sacrificial IP addresses to effectively disable blocklistd before launching an attack.
Even in the absence of attacks or probes by would-be attackers, adverse events will occur regularly in the course of normal operations, and blocklistd will gradually run out file descriptors and become ineffective.
The accumulation of open sockets may have knock-on effects on other parts of the system, resulting in a general slowdown until blocklistd is restarted. |
| Buffer overflow in ncurses 5.0, and the ncurses4 compatibility package as used in Red Hat Linux, allows local users to gain privileges, related to "routines for moving the physical cursor and scrolling." |
| Heap corruption vulnerability in the "at" program allows local users to execute arbitrary code via a malformed execution time, which causes at to free the same memory twice. |
| cpio on FreeBSD 2.1.0, Debian GNU/Linux 3.0, and possibly other operating systems, uses a 0 umask when creating files using the -O (archive) or -F options, which creates the files with mode 0666 and allows local users to read or overwrite those files. |
| Multiple TCP implementations could allow remote attackers to cause a denial of service (bandwidth and CPU exhaustion) by setting the maximum segment size (MSS) to a very small number and requesting large amounts of data, which generates more packets with less TCP-level data that amplify network traffic and consume more server CPU to process. |
| Some AIO operations in FreeBSD 4.4 may be delayed until after a call to execve, which could allow a local user to overwrite memory of the new process and gain privileges. |
| FreeBSD 3.2 and possibly other versions allows a local user to cause a denial of service (panic) with a large number accesses of an NFS v3 mounted directory from a large number of processes. |
| OpenBSD, BSDI, and other Unix operating systems allow users to set chflags and fchflags on character and block devices. |
| FreeBSD 4.3 does not properly clear shared signal handlers when executing a process, which allows local users to gain privileges by calling rfork with a shared signal handler, having the child process execute a setuid program, and sending a signal to the child. |
| linprocfs on FreeBSD 4.3 and earlier does not properly restrict access to kernel memory, which allows one process with debugging rights on a privileged process to read restricted memory from that process. |
| Operating systems with shared memory implementations based on BSD 4.4 code allow a user to conduct a denial of service and bypass memory limits (e.g., as specified with rlimits) using mmap or shmget to allocate memory and cause page faults. |
| TCP Wrappers (tcp_wrappers) in FreeBSD 4.1.1 through 4.3 with the PARANOID ACL option enabled does not properly check the result of a reverse DNS lookup, which could allow remote attackers to bypass intended access restrictions via DNS spoofing. |
| fts routines in FreeBSD 4.3 and earlier, NetBSD before 1.5.2, and OpenBSD 2.9 and earlier can be forced to change (chdir) into a different directory than intended when the directory above the current directory is moved, which could cause scripts to perform dangerous actions on the wrong directories. |
| runtar in the Amanda backup system used in various UNIX operating systems executes tar with root privileges, which allows a user to overwrite or read arbitrary files by providing the target files to runtar. |
| The rwho/rwhod service is running, which exposes machine status and user information. |
| Buffer overflow in rwhod on AIX and other operating systems allows remote attackers to execute arbitrary code via a UDP packet with a long hostname. |
| Format string vulnerability in Hylafax on FreeBSD allows local users to execute arbitrary code via format specifiers in the -h hostname argument for (1) faxrm or (2) faxalter. |
