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.
https://www.openwall.com/lists/oss-security/2025/01/14/3
https://thehackernews.com/2025/01/google-cloud-researchers-uncover-flaws.html
https://kb.cert.org/vuls/id/952657
https://bugzilla.redhat.com/show_bug.cgi?id=2330527