CVE-2026-53798 rsync < 3.5.0 Privilege Confusion via name-converter uid/gid mapping

What is CVE-2026-53798?

CVE-2026-53798 is a medium-severity vulnerability in RsyncProject rsync, published on 13 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

rsync before 3.5.0 contains a privilege confusion vulnerability in the name-converter subprocess uid/gid mapping that allows local attackers to cause transferred files to be owned by root by influencing name-converter responses to return empty values. When the name-converter subprocess returns an empty response for a uid or gid lookup, rsync incorrectly interprets it as a successful resolution to uid/gid 0 (root) rather than a lookup failure, and if the name-converter also signals fake super-user status, rsync proceeds with root ownership assignments for transferred files.

Weakness: CWE-704

Which versions are affected by CVE-2026-53798?

It affects 1 product.

Products include Samba Rsync.

How do I fix CVE-2026-53798?

Upgrade to a fixed version.

Is CVE-2026-53798 being exploited?

There is no known exploitation of CVE-2026-53798 in the wild and no public exploit code.

Other vulnerabilities in RsyncProject rsync

• CVE-2017-15994 Security feature bypass in n/a Critical 9.8
• CVE-2026-53791 rsync < 3.5.0 Daemon IP Spoofing via PROXY Protocol Header Critical 9.1
• CVE-2026-70461 rsync 3.2.5 < 3.5.0 Heap Out-of-Bounds Write via files-from Entry High 8.8
• CVE-2026-70455 rsync 3.4.2 < 3.5.0 DoS via --zt Zstandard Compression Thread Exhaustion High 8.7
• CVE-2026-70463 rsync 3.1.0 < 3.5.0 Authorization Bypass via auth users Directive Parsing High 8.6

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as ALPINE-CVE-2026-53798, AZL-95804, BELL-CVE-2026-53798, DEBIAN-CVE-2026-53798, ECHO-2583-309c-2ae2, GHSA-hx7p-3gvv-pqgv and 1 more.