Vulnerability Description
Rsync version 3.4.2 and prior contain an authorization bypass vulnerability in the rsync daemon's hostname-based access control list enforcement when configured with chroot. Attackers can bypass hostname-based deny rules by controlling the PTR record for their source IP address, allowing connections from hostnames that administrators intended to deny when reverse DNS resolution fails and defaults to UNKNOWN.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Samba | Rsync | <= 3.4.2 |
Related Weaknesses (CWE)
References
- https://github.com/RsyncProject/rsync/releases/tag/v3.4.3Release Notes
- https://github.com/RsyncProject/rsync/security/advisories/GHSA-rjfm-3w2m-jf4fVendor Advisory
- https://www.vulncheck.com/advisories/rsync-authorization-bypass-via-hostname-resThird Party Advisory
FAQ
What is CVE-2026-43617?
CVE-2026-43617 is a vulnerability with a CVSS score of 4.8 (MEDIUM). Rsync version 3.4.2 and prior contain an authorization bypass vulnerability in the rsync daemon's hostname-based access control list enforcement when configured with chroot. Attackers can bypass hostn...
How severe is CVE-2026-43617?
CVE-2026-43617 has been rated MEDIUM with a CVSS base score of 4.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-43617?
Check the references section above for vendor advisories and patch information. Affected products include: Samba Rsync.