Vulnerability in Rsyncproject Rsync
CVE-2026-29518
Rsync versions before 3.4.3 contain a time-of-check to time-of-use (TOCTOU) race condition in daemon file handling that allows attackers to redirect file writes outside intended directories by replacing parent directory components with symbolic links. Attackers with write access to a module path can exploit this race condition to create or overwrite arbitrary files, potentially modifying sensitive system files and achieving privilege escalation when the daemon runs with elevated privileges. This vulnerability can only be triggered if the chroot setting is false.
Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)
EPSS: 0.002 (4.6th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.0 (High). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Rsyncproject Rsync — versions 0
- Samba Rsync
Weakness classification (CWE)
References
- disclosure@vulncheck.com (issue-tracking, Patch)
- disclosure@vulncheck.com (release-notes, Release Notes)
- disclosure@vulncheck.com (Third Party Advisory, third-party-advisory)
- disclosure@vulncheck.com (technical-description)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Frequently asked questions
- What is CVE-2026-29518?
- CVE-2026-29518 is a high-severity vulnerability in Rsyncproject Rsync, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 7.0/10. Published 2026-05-20.
- How severe is CVE-2026-29518?
- High severity. CVSS v3 base score is 7.0 out of 10.