Buffer overflow in Rsyncproject Rsync
CVE-2026-53792
rsync before 3.5.0 contains an out-of-bounds read vulnerability in the sender-side block matching logic that allows a malicious receiver to trigger memory access before the start of an allocated buffer by sending a crafted checksum block with a length of zero. Attackers can send a specially crafted checksum set containing a zero-length block to cause a negative offset calculation during delta computation, resulting in an out-of-bounds read of file data buffer memory on the sender side.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.005 (36.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 37th percentile — 36.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · 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-cg57-rp9g-56hw (vendor-advisory)
- www.vulncheck.com/advisories/rsync-out-of-bounds-read-via-zero-length-checksum-… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-53792?
- CVE-2026-53792 is a medium-severity vulnerability in Rsyncproject Rsync, classified under Improper Validation of Array Index. CVSS score: 6.5/10. Published 2026-08-13.
- How severe is CVE-2026-53792?
- Medium severity. CVSS v3 base score is 6.5 out of 10.