ASA-2019-00597 – OpenSSH: Pre-Auth XMSS Integer Overflow

OpenSSH 7.7 through 7.9 and 8.x before 8.1, when compiled with an experimental key type, has a pre-authentication integer overflow if a client or server is configured to use a crafted XMSS key. This leads to memory corruption and local code execution because of an error in the XMSS key parsing algorithm.

ASA-2019-00574 – libssh2: Out-of-bounds read when connecting to a malicious SSH server

There is an out-of-bounds read vulnerability, potentially leading to either denial of service or remote information disclosure. It is triggered when libssh2 is used to connect to a malicious SSH server. The overflow occurs when the SSH server sends a disconnect message, which means that the vulnerability can be triggered early in the connection process, before authentication is completed.

ASA-2019-00548 – WhatsApp: Integer overflow in media parsing libraries via specially-crafted EXIF tags in WEBP images

An integer overflow in WhatsApp media parsing libraries allows a remote attacker to perform an out-of-bounds write on the heap via specially-crafted EXIF tags in WEBP images.

ASA-2019-00506 – Wind River VxWorks: TCP Urgent Pointer = 0 leads to integer underflow

A specially crafted TCP-segment with the URG-flag set may cause overflow of the buffer passed to recv(), recvfrom() or recvmsg() socket routines. With a prerequisite that the system uses TCP sockets, an attacker can either hijack an existing TCP session and inject bad TCP segments, or establish a new TCP session on any TCP port the victim system listens to. The impact of the vulnerability is a buffer overflow of up to a full TCP receive-windows (by default 10k-64k depending on the version). The buffer overflow happens in the task calling recv()/recvfrom()/recvmsg(). Applications that pass a buffer equal to or larger than a full TCP window are not susceptible to this attack. Applications passing a stack-allocated variable as buffer are the easiest to exploit. The most likely outcome is a crash of the application reading from the affected socket. In the worst-case scenario, this vulnerability can potentially lead to RCE.

ASA-2019-00463 – libssh2: Out-of-bounds read leading to information disclosure

In libssh2 before 1.9.0, the function kex_method_diffie_hellman_group_exchange_sha256 _key_exchange() in the file kex.c has an integer overflow that could lead to an out-of-bounds read in the way packets are read from the server. A remote attacker who compromises a SSH server may be able to disclose sensitive information or cause a denial of service condition on the client system when a user connects to the server.

ASA-2019-00406 – VMware: Selective Acknowledgement (SACK) Panic

A sequence of SACKs may be crafted such that one can trigger an integer overflow, leading to a kernel panic.  A malicious actor must have network access to an affected system including the ability to send traffic with low MSS values to the target. Successful exploitation of these issues may cause the target system to crash or significantly degrade performance.

ASA-2019-00365 – Linux kernel: Integer overflow while processing SACK blocks allows remote denial of service (SACK Panic)

An integer overflow flaw was found in the way the Linux kernel's networking subsystem processed TCP Selective Acknowledgment (SACK) segments. While processing SACK segments, the Linux kernel's socket buffer (SKB) data structure becomes fragmented. Each fragment is about TCP maximum segment size (MSS) bytes. To efficiently process SACK blocks, the Linux kernel merges multiple fragmented SKBs into one, potentially overflowing the variable holding the number of segments. A remote attacker could use this flaw to crash the Linux kernel by sending a crafted sequence of SACK segments on a TCP connection with small value of TCP MSS, resulting in a denial of service (DoS).