CVE-2026-53791
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.
Package Versions Affected
Automatically patch vulnerabilities without upgrading
CVSS Version



Related Resources
References
https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53791.json, https://github.com/RsyncProject/rsync/releases/tag/v3.5.0, https://github.com/RsyncProject/rsync/security/advisories/GHSA-h2q9-5fr8-w635, https://nvd.nist.gov/vuln/detail/CVE-2026-53791, https://www.vulncheck.com/advisories/rsync-daemon-ip-spoofing-via-proxy-protocol-header, https://github.com/RsyncProject/rsync