CVE-2026-43620

Rsync version 3.4.2 and prior contain a receiver-side out-of-bounds array read vulnerability in recv_files() in receiver.c that allows a malicious rsync server to crash the rsync client process. Attackers can exploit the vulnerability by setting CF_INC_RECURSE in compatibility flags and sending a specially crafted file list where the first sorted entry is not the leading dot directory, followed by a transfer record with ndx=0 and an iflag word without ITEM_TRANSFER, causing the receiver to read 8 bytes before the allocated pointer array and dereference an invalid pointer at an unmapped address, resulting in a deterministic SIGSEGV crash of the rsync client.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/RsyncProject/rsync/releases/tag/v3.4.3	Release Notes
https://github.com/RsyncProject/rsync/security/advisories/GHSA-28pw-r563-rxvm	Vendor Advisory
https://www.vulncheck.com/advisories/rsync-out-of-bounds-array-read-via-recv-files	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:samba:rsync:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-20 02:16

Updated : 2026-07-24 09:10

NVD link : CVE-2026-43620

Mitre link : CVE-2026-43620

CVE.ORG link : CVE-2026-43620

JSON object : View

Products Affected

samba

rsync

CWE

CWE-125

Out-of-bounds Read

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