Vulnerability in Rsyncproject Rsync
CVE-2026-70454
rsync 3.2.0 through 3.2.3 (openssl mode) and rsync-ssl through 3.4.4 (stunnel mode) contain a TLS certificate validation vulnerability that allows on-path attackers to intercept encrypted sessions by presenting self-signed or otherwise invalid certificates. Attackers can exploit the failure to validate server TLS certificates against a trusted CA or verify certificate hostname matching to decrypt or tamper with rsync session content without detection by the client.
Vulnerability class: Improper Certificate Validation
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.0 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.002 (14.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 14th percentile — 14.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.001
Affected products
- Rsyncproject Rsync — versions 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-3c3x-ww2w-5r5p (vendor-advisory)
- www.vulncheck.com/advisories/rsync-tls-certificate-validation-bypass-via-ssl-op… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-70454?
- CVE-2026-70454 is a high-severity vulnerability in Rsyncproject Rsync, classified under Improper Certificate Validation. CVSS score: 8.0/10. Published 2026-08-13.
- How severe is CVE-2026-70454?
- High severity. CVSS v3 base score is 8.0 out of 10.