A flaw was found in libssh in which a malicious SFTP (SSH File Transfer Protocol) server can exploit this by sending a malformed 'longname' field within an SSHFXPNAME message during a file listing operation. This missing null check can lead to reading beyond allocated memory on the heap. This can cause unexpected behavior or lead to a denial of service (DoS) due to application crashes.

A flaw was found in libssh where it can attempt to open arbitrary files during configuration parsing. A local attacker can exploit this by providing a malicious configuration file or when the system is misconfigured. This vulnerability could lead to a Denial of Service (DoS) by causing the system to try and access dangerous files, such as block devices or large system files, which can disrupt normal operations.

A flaw was found in libssh. A remote attacker, by controlling client configuration files or knownhosts files, could craft specific hostnames that when processed by the matchpattern() function can lead to inefficient regular expression backtracking. This can cause timeouts and resource exhaustion, resulting in a Denial of Service (DoS) for the client.

A weakness has been identified in libssh up to 0.11.3. The impacted element is the function sftpextensionsgetname/sftpextensionsgetdata of the file src/sftp.c of the component SFTP Extension Name Handler. Executing a manipulation of the argument idx can lead to out-of-bounds read. The attack may be performed from remote. Upgrading to version 0.11.4 and 0.12.0 is sufficient to resolve this issue. This patch is called 855a0853ad3abd4a6cd85ce06fce6d8d4c7a0b60. You should upgrade the affected component.