Vulnerability in Rsyncproject Rsync
CVE-2026-53803
rsync before 3.5.0 contains a symlink following vulnerability that allows local attackers to overwrite arbitrary files by placing a symlink at a predictable output path such as --log-file, --write-batch, or daemon-mode log and statistics paths. Attackers can exploit rsync's failure to reject symlinks during ancillary file writes to redirect output to arbitrary filesystem locations, achieving local privilege escalation on installations where rsync runs with elevated privileges such as setuid or privileged daemon configurations.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.002 (10.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 10th percentile — 10.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000
Affected products
- Rsyncproject Rsync — versions 0, 3.5.0
- Samba Rsync
Weakness classification (CWE)
References
- github.com/RsyncProject/rsync/releases/tag/v3.5.0 (release-notes, Product, Release Notes)
- github.com/RsyncProject/rsync/security/advisories/GHSA-g9f4-7q66-9582 (vendor-advisory, Vendor Advisory)
- www.vulncheck.com/advisories/rsync-symlink-following-arbitrary-file-overwrite (Third Party Advisory, Release Notes, third-party-advisory)
Frequently asked questions
- What is CVE-2026-53803?
- CVE-2026-53803 is a high-severity vulnerability in Rsyncproject Rsync, classified under Improper Link Resolution Before File Access. CVSS score: 7.8/10. Published 2026-08-13.
- How severe is CVE-2026-53803?
- High severity. CVSS v3 base score is 7.8 out of 10.