| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| 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. |
| 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. |
| 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. |
| 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. |
| 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. |
| The access permissions for a UNIX domain socket are ignored in Solaris 2.x and SunOS 4.x, and other BSD-based operating systems before 4.4, which could allow local users to connect to the socket and possibly disrupt or control the operations of the program using that socket. |
| Buffer overflow in ppp program in FreeBSD 2.1 and earlier allows local users to gain privileges via a long HOME environment variable. |
| ICMP messages to broadcast addresses are allowed, allowing for a Smurf attack that can cause a denial of service. |
| Vulnerability when Network Address Translation (NAT) is enabled in Linux 2.2.10 and earlier with ipchains, or FreeBSD 3.2 with ipfw, allows remote attackers to cause a denial of service (kernel panic) via a ping -R (record route) command. |
| Vulnerability in union file system in FreeBSD 2.2 and earlier, and possibly other operating systems, allows local users to cause a denial of service (system reload) via a series of certain mount_union commands. |
| A buffer overflow in lsof allows local users to obtain root privilege. |
| pcnfsd (aka rpc.pcnfsd) allows local users to change file permissions, or execute arbitrary commands through arguments in the RPC call. |
| Buffer overflow in Xt library of X Windowing System allows local users to execute commands with root privileges. |
| Manual page reader (man) in FreeBSD 2.2 and earlier allows local users to gain privileges via a sequence of commands. |
| A design flaw in the Z-Modem protocol allows the remote sender of a file to execute arbitrary programs on the client, as implemented in rz in the rzsz module of FreeBSD before 2.1.5, and possibly other programs. |
