Arch Linux Security Advisory ASA-202501-1
=========================================
Severity: Critical
Date : 2025-01-14
CVE-ID : CVE-2024-12084 CVE-2024-12085 CVE-2024-12086 CVE-2024-12087
CVE-2024-12088 CVE-2024-12747
Package : rsync
Type : multiple issues
Remote : Yes
Link : https://security.archlinux.org/AVG-2858
Summary
=======
The package rsync before version 3.4.0-1 is vulnerable to multiple
issues including arbitrary code execution, arbitrary file upload,
information disclosure and privilege escalation.
Resolution
==========
Upgrade to 3.4.0-1.
# pacman -Syu "rsync>=3.4.0-1"
The problems have been fixed upstream in version 3.4.0.
Workaround
==========
None.
Description
===========
- CVE-2024-12084 (arbitrary code execution)
A heap-based buffer overflow flaw was found in the rsync daemon. This
issue is due to improper handling of attacker-controlled checksum
lengths (s2length) in the code. When MAX_DIGEST_LEN exceeds the fixed
SUM_LENGTH (16 bytes), an attacker can write out of bounds in the sum2
buffer.
- CVE-2024-12085 (information disclosure)
A flaw was found in the rsync daemon 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.
- CVE-2024-12086 (information disclosure)
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.
- CVE-2024-12087 (arbitrary file upload)
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.
- CVE-2024-12088 (arbitrary file upload)
A flaw was found in rsync. When using the --safe-links option, rsync
fails to properly verify if a symbolic link destination contains
another symbolic link within it. This results in a path traversal
vulnerability, which may lead to arbitrary file write outside the
desired directory.
- CVE-2024-12747 (privilege escalation)
A flaw was found in rsync. This vulnerability arises from a race
condition during rsync's handling of symbolic links. Rsync's default
behavior when encountering symbolic links is to skip them. If an
attacker replaced a regular file with a symbolic link at the right
time, it was possible to bypass the default behavior and traverse
symbolic links. Depending on the privileges of the rsync process, an
attacker could leak sensitive information, potentially leading to
privilege escalation.
Impact
======
A remote attacker is able to execute arbitrary code on a device that
has an Rsync server running. The client requires only anonymous read-
access to the server, such as public mirrors.
Additionally, attackers can take control of a malicious server and
read/write arbitrary files of any connected client. Sensitive data,
such as OpenPGP and SSH keys, can be extracted, and malicious code can
be executed by overwriting files such as ~/.bashrc or ~/.popt.
References
==========
https://kb.cert.org/vuls/id/952657https://www.openwall.com/lists/oss-security/2025/01/14/3https://download.samba.org/pub/rsync/NEWS#3.4.0https://security.archlinux.org/CVE-2024-12084https://security.archlinux.org/CVE-2024-12085https://security.archlinux.org/CVE-2024-12086https://security.archlinux.org/CVE-2024-12087https://security.archlinux.org/CVE-2024-12088https://security.archlinux.org/CVE-2024-12747