CVE-2026-53791
published 2026-08-13CVE-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…
PriorityP265critical9.1CVSS 3.1
AVNACLPRNUINSUCHIHAN
EPSS
0.50%
41.1th percentile
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.
Affected
3 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| rsyncproject | rsync | <= 3.4.4 | — |
| samba | rsync | < 3.5.0 | 3.5.0 |
| samba | rsync | — | — |
CVSS provenance
nvdv3.19.1CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
nvdv4.09.1CRITICALCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
vendor_redhat9.1CRITICAL
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Bugzilla
CVE-2026-53791 rsync: rsync < 3.5.0 Daemon IP Spoofing via PROXY Protocol Header [fedora-all]
bugzilla·2026-08-21·CVSS 9.1
CVE-2026-53791 [CRITICAL] CVE-2026-53791 rsync: rsync < 3.5.0 Daemon IP Spoofing via PROXY Protocol Header [fedora-all]
CVE-2026-53791 rsync: rsync < 3.5.0 Daemon IP Spoofing via PROXY Protocol Header [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
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.
Disc
Bugzilla
CVE-2026-53791 rsync: rsync < 3.5.0 Daemon IP Spoofing via PROXY Protocol Header
bugzilla·2026-08-13·CVSS 9.1
CVE-2026-53791 [CRITICAL] CVE-2026-53791 rsync: rsync < 3.5.0 Daemon IP Spoofing via PROXY Protocol Header
CVE-2026-53791 rsync: rsync < 3.5.0 Daemon IP Spoofing via PROXY Protocol Header
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.
2026-08-13
Published