CVE-2026-53791: rsync daemon before 3.5.0 contains an IP address spoofing vulnerability that allows unauthenticated remote attackers…
CVE-2026-53791 · Severity: critical · CVSS 9.1 · Published 2026-08-13
rsync daemon before 3.5.0 contains an IP address spoofing vulnerability that allows unauthenticated remote attackers to bypass IP-based access controls by sending a crafted PROXY protocol header with a forged source address. Attackers who can connect directly to the rsync daemon can inject a spoofed source IP in the PROXY protocol header to circumvent hosts allow/deny rules, gaining unauthorized access that would otherwise be blocked based on their real source address.
No. Junglewise Threat Intelligence has no report of CVE-2026-53791 being exploited in the wild.
How severe is CVE-2026-53791?
Critical severity, with a CVSS score of 9.1, published 13 August 2026.
Which products and versions are affected?
Samba Rsync. The advisory does not name versions.
Is there a fix for CVE-2026-53791?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
Am I affected by CVE-2026-53791?
Check whether you run Samba Rsync. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.