CVE-2026-53792

MEDIUM 6.5

rsync < 3.5.0 Out-of-Bounds Read via Zero-Length Checksum Block

CVSS Score

6.5

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-129 CWE-787
Vendor	rsyncproject
Product	rsync
Published	Aug 13, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Affected Versions

RsyncProject / rsync

0 ≤ 3.4.4

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/RsyncProject/rsync/security/advisories/GHSA-cg57-rp9g-56hw github.com: https://github.com/RsyncProject/rsync/releases/tag/v3.5.0 vulncheck.com: https://www.vulncheck.com/advisories/rsync-out-of-bounds-read-via-zero-length-checksum-block

Credits

akoul z3r0s6