Off-by-one Error Affecting rsync package, versions <3.4.3-r0


Severity

Recommended
0.0
low
0
10

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Threat Intelligence

EPSS
0.34% (26th percentile)

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  • Snyk IDSNYK-ALPINE321-RSYNC-16780680
  • published21 May 2026
  • disclosed20 May 2026

Introduced: 20 May 2026

CVE-2026-45232  (opens in a new tab)
CWE-193  (opens in a new tab)

How to fix?

Upgrade Alpine:3.21 rsync to version 3.4.3-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream rsync package and not the rsync package as distributed by Alpine. See How to fix? for Alpine:3.21 relevant fixed versions and status.

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 Base Scores

version 3.1