CVE-2026-53803

High [CVE-2026-53803] Local Privilege Escalation via Symlink Following

CVE-2026-53803Source published Aug 13, 2026Source updated Aug 13, 2026

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. This Important vulnerability in rsync allows a local attacker to achieve privilege escalation by exploiting a symlink following flaw. In Red Hat environments, the risk is elevated when rsync is configured to run with elevated privileges, such as setuid or in daemon…

Affected products in this advisory

• Red Hat Enterprise Linux 10
• Red Hat Enterprise Linux 9
• Red Hat Enterprise Linux 6
• Red Hat Enterprise Linux 7

3 more entries in the full advisory.

Source-reported affected versions

• < 3.5.0

Source-reported fixed versions

• 3.5.0
• rsync-0:3.5.0-3.el10_2
• rsync-0:3.2.7-1.el9_8
• RHSA-2026:67463

1 more entries in the full advisory.

Mitigation guidance

• Do not run rsync setuid or point output paths (--log-file, --write-batch, or daemon config/log files) to user-writable directories like /tmp. While fs.protected_symlinks=1 prevents simple symlink creation in sticky directories on RHEL 7+, it does not stop parent-component attacks in standard directories. If the rsyncd daemon is unneeded, disable it (systemctl disable --now rsyncd); if required, enforce least-privilege execution and restrict network access to trusted hosts.