Rsync < 3.4.3 Out-of-Bounds Array Read via recv_files()_CVE-2026-43620

6.9 / 10

MEDIUM

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Description

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.

Basic Information

ID CVE-2026-43620

Source VulnCheck

Published May 20, 2026 at 00:47

Affected Product

Vendor RsyncProject

Product rsync

Affected Versions RsyncProject rsync 0

CWE Classification

CWE-125

References

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    "published": "2026-05-20T00:47:57.086Z",
    "modified": "2026-05-20T00:47:57.086Z",
    "type": "cve",
    "title": "Rsync < 3.4.3 Out-of-Bounds Array Read via recv_files()",
    "source": "VulnCheck",
    "references": "https://github.com/RsyncProject/rsync/security/advisories/GHSA-28pw-r563-rxvm\nhttps://github.com/RsyncProject/rsync/releases/tag/v3.4.3\nhttps://www.vulncheck.com/advisories/rsync-out-of-bounds-array-read-via-recv-files",
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