Auth bypass in Rsyncproject Rsync
CVE-2026-70452
rsync 3.1.0 before 3.5.0 contains an access control bypass vulnerability that allows remote attackers to circumvent hosts deny rules by inducing DNS resolution failures during hostname-based access control evaluation. When a DNS lookup for a hostname-based deny rule fails, the daemon skips the rule rather than defaulting to a deny decision, enabling attackers who can trigger DNS failures to bypass module-level IP access controls and gain unauthorized access to restricted module file trees.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.006 (44.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 44th percentile — 44.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.006 · change: +0.001
Affected products
- Rsyncproject Rsync — versions 3.1.0, 3.5.0
Weakness classification (CWE)
References
- github.com/RsyncProject/rsync/releases/tag/v3.5.0 (release-notes)
- github.com/RsyncProject/rsync/security/advisories/GHSA-6692-28cx-wpqq (vendor-advisory)
- www.vulncheck.com/advisories/rsync-access-control-bypass-via-dns-resolution-fai… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-70452?
- CVE-2026-70452 is a high-severity vulnerability in Rsyncproject Rsync, classified under CWE-636. CVSS score: 7.4/10. Published 2026-08-13.
- How severe is CVE-2026-70452?
- High severity. CVSS v3 base score is 7.4 out of 10.