CVE-2026-53783

high

Description

rsync before 3.5.0 contains a time-of-check to time-of-use (TOCTOU) race condition vulnerability in the rrsync restricted shell wrapper that allows authenticated clients to escape enforced directory restrictions by substituting a symlink for a path component after validation but before transfer processing. Attackers can additionally leverage unrestricted flags such as --copy-unsafe-links, -D, and --log-file through rrsync to read or write files outside the permitted directory subtree.

References

https://www.vulncheck.com/advisories/rsync-toctou-race-condition-directory-escape-via-rrsync

https://github.com/RsyncProject/rsync/security/advisories/GHSA-9cgc-64g4-3gv5

https://github.com/RsyncProject/rsync/releases/tag/v3.5.0

Details

Source: Mitre, NVD

Published: 2026-08-13

Updated: 2026-08-13

Risk Information

CVSS v2

Base Score: 8.5

Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:N

Severity: High

CVSS v3

Base Score: 8.1

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Severity: High

CVSS v4

Base Score: 8.6

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

Severity: High