Time-of-check Time-of-use (TOCTOU) Race Condition in Rsync - CVE-2026-53796

Vulnerability identifier: #VU142283

CSH Severity: Low

CVSS v4: 5.8 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-53796

CWE-ID: CWE-367

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to overwrite files outside the destination tree.

The vulnerability exists due to a time-of-check time-of-use race condition in the non-daemon receiver destination chdir handling when processing an operator-named destination directory. A local user can race the destination path from a directory to a symlink pointing outside the destination tree to overwrite files outside the destination tree.

This issue affects non-daemon receiver operation and can lead to local privilege escalation in scenarios such as privileged scheduled rsync runs over an attacker-controlled destination component.

Rsync
Debian Linux
SUSE Linux Enterprise Server 15 SP6
SUSE Linux Enterprise Server 15 SP5
SUSE Linux Enterprise Server 15 SP4
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise High Performance Computing 15
SUSE Linux Enterprise High Performance Computing LTSS 15
SUSE Linux Enterprise High Performance Computing ESPOS 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Micro
SUSE Linux Enterprise Micro for Rancher
Basesystem Module
openSUSE Leap
openEuler
Fedora
rsync-debugsource
rsync-debuginfo
rsync
rsync-help
rsync (Debian package)

Install security update from vendor's website.

Rsync - update to 3.5.0
rsync-debugsource - addressed in versions 3.2.3-150400.3.34.1, 3.2.7-150600.3.24.1
rsync-debuginfo - addressed in versions 3.2.3-150400.3.34.1, 3.2.7-150600.3.24.1
rsync - addressed in versions 3.2.3-150400.3.34.1, 3.2.7-150600.3.24.1
rsync-debugsource - update to 3.2.7-12
rsync-help - update to 3.2.7-12
rsync-debuginfo - update to 3.2.7-12
rsync - update to 3.2.7-12
rsync (Debian package) - update to 3.5.0+ds1-0+deb13u1
rsync - addressed in versions 3.5.0-1.fc43, 3.5.0-1.fc44

• https://github.com/RsyncProject/rsync/security/advisories/GHSA-w75h-ccff-w53m

• Multiple vulnerabilities in Rsync
• SUSE update for rsync
• Fedora 44 update for rsync
• Fedora 43 update for rsync
• SUSE update for rsync
• openEuler 24.03 LTS SP3 update for rsync
• openEuler 24.03 LTS SP1 update for rsync
• openEuler 24.03 LTS SP4 update for rsync
• Debian update for rsync