PT-2026-55847 · Julia · Rsync Jll

Published 2026-06-25 · Updated 2026-06-25

OSV

CVSS v4.0

2.1

Low

Base vector

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

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.

Fix

Related Identifiers

JLSEC-2026-632

Affected Products

Rsync Jll

References · 4

• https://osv.dev/vulnerability/JLSEC-2026-632 · Vendor Advisory
• https://github.com/RsyncProject/rsync/releases/tag/v3.4.3 · Note
• https://github.com/RsyncProject/rsync/security/advisories/GHSA-8f85-j2cv-59m8 · Note
• https://vulncheck.com/advisories/rsync-off-by-one-stack-write-via-http-proxy · Note