rsync daemon before 3.5.0 contains an IP address spoofing vulnerability that allows unauthenticated remote attackers
Affects rsyncSource GCVE Database
Not known to be exploited · CVSS 9.1 Critical · fixed in 3.5.0 : patch rsync as a priority.
Data as of 13 Nov 2026, 21:41 UTC
- Patch
- Available – fixed in 3.5.0
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 13 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSrsyncpkg:deb/ubuntu/rsync?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSrsyncpkg:deb/ubuntu/rsync?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSrsyncpkg:deb/ubuntu/rsync?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu Pro 20.04 LTSrsyncpkg:deb/ubuntu/rsync?arch=source&distro=esm-infra/focalOther threats | Affected
| Fixed in– |
Ubuntu Pro 18.04 LTSrsyncpkg:deb/ubuntu/rsync?arch=source&distro=esm-infra/bionicOther threats | Affected
| Fixed in– |
Ubuntu Pro 16.04 LTSrsyncpkg:deb/ubuntu/rsync?arch=source&distro=esm-infra-legacy/xenialOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available in rsync version 3.5.0 and later. Users should upgrade to version 3.5.0 or newer to remediate this vulnerability. Since this is a software flaw in the rsync daemon, patching the software is the recommended mitigation. No vendor advisory content was provided to indicate alternative mitigations or temporary workarounds.
Description
A critical IP address spoofing vulnerability exists in rsync daemon versions before 3.5.0. This flaw allows unauthenticated remote attackers to bypass IP-based access controls by sending a crafted PROXY protocol header with a forged source IP address. Exploiting this vulnerability enables attackers who can connect directly to the rsync daemon to circumvent host allow/deny rules and gain unauthorized access that would otherwise be blocked.