rsync

A flaw was found in rsync which could be triggered when rsync compares file checksums. This flaw allows an attacker to manipulate the checksum length (s2length) to cause a comparison between a checksum and uninitialized memory and leak one byte of uninitialized stack data at a time.

The parse_arguments function in options.c in rsyncd in rsync before 3.1.3 does not prevent multiple --protect-args uses, which allows remote attackers to bypass an argument-sanitization protection mechanism.

An issue was discovered in rsync before 3.2.5 that allows malicious remote servers to write arbitrary files inside the directories of connecting peers. The server chooses which files/directories are sent to the client. However, the rsync client performs insufficient validation of file names. A malicious rsync server (or Man-in-The-Middle attacker) can overwrite arbitrary files in the rsync client target directory and subdirectories (for example, overwrite the .ssh/authorized_keys file).

A flaw was found in rsync in versions since 3.2.0pre1. Rsync improperly validates certificate with host mismatch vulnerability. A remote, unauthenticated attacker could exploit the flaw by performing a man-in-the-middle attack using a valid certificate for another hostname which could compromise confidentiality and integrity of data transmitted using rsync-ssl. The highest threat from this vulnerability is to data confidentiality and integrity. This flaw affects rsync versions before 3.2.4.

A path traversal vulnerability exists in rsync. It stems from behavior enabled by the `--inc-recursive` option, a default-enabled option for many client options and can be enabled by the server even if not explicitly enabled by the client. When using the `--inc-recursive` option, a lack of proper symlink verification coupled with deduplication checks occurring on a per-file-list basis could allow a server to write files outside of the client's intended destination directory. A malicious server could write malicious files to arbitrary locations named after valid directories/paths on the client.

A flaw was found in rsync. When using the `--safe-links` option, the rsync client fails to properly verify if a symbolic link destination sent from the server contains another symbolic link within it. This results in a path traversal vulnerability, which may lead to arbitrary file write outside the desired directory.

A flaw was found in rsync. It could allow a server to enumerate the contents of an arbitrary file from the client's machine. This issue occurs when files are being copied from a client to a server. During this process, the rsync server will send checksums of local data to the client to compare with in order to determine what data needs to be sent to the server. By sending specially constructed checksum values for arbitrary files, an attacker may be able to reconstruct the data of those files byte-by-byte based on the responses from the client.