CVE-2026-45232

Rsync versions before 3.4.3 contain an off-by-one out-of-bounds stack write vulnerability in the establish_proxy_connection() function in socket.c that allows network attackers to corrupt stack memory by sending a malformed HTTP proxy response. Attackers can exploit this by positioning themselves between the client and proxy or controlling the proxy server to send a response line of 1023 or more bytes without a newline terminator, causing a null byte to be written to an out-of-bounds stack address when the RSYNC_PROXY environment variable is set.

CVSS v3 3.1 LOW

3.1^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.6 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

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-8f85-j2cv-59m8	Vendor Advisory
https://www.vulncheck.com/advisories/rsync-off-by-one-stack-write-via-http-proxy	Third Party Advisory

Configurations

Configuration 1 (hide)

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

History

21 May 2026, 20:52

Type	Values Removed	Values Added
CPE		cpe:2.3:a:samba:rsync::::::::
First Time		Samba Samba rsync
References	~~() https://github.com/RsyncProject/rsync/releases/tag/v3.4.3 -~~	() https://github.com/RsyncProject/rsync/releases/tag/v3.4.3 - Release Notes
References	~~() https://github.com/RsyncProject/rsync/security/advisories/GHSA-8f85-j2cv-59m8 -~~	() https://github.com/RsyncProject/rsync/security/advisories/GHSA-8f85-j2cv-59m8 - Vendor Advisory
References	~~() https://www.vulncheck.com/advisories/rsync-off-by-one-stack-write-via-http-proxy -~~	() https://www.vulncheck.com/advisories/rsync-off-by-one-stack-write-via-http-proxy - Third Party Advisory

20 May 2026, 02:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-20 02:16

Updated : 2026-05-21 20:52

NVD link : CVE-2026-45232

Mitre link : CVE-2026-45232

CVE.ORG link : CVE-2026-45232

JSON object : View

Products Affected

samba

rsync

CWE

CWE-193

Off-by-one Error

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