CVE-2026-53783

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.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/RsyncProject/rsync/releases/tag/v3.5.0
https://github.com/RsyncProject/rsync/security/advisories/GHSA-9cgc-64g4-3gv5
https://www.vulncheck.com/advisories/rsync-toctou-race-condition-directory-escape-via-rrsync

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-13 15:19

Updated : 2026-09-08 20:28

NVD link : CVE-2026-53783

Mitre link : CVE-2026-53783

CVE.ORG link : CVE-2026-53783

JSON object : View

Products Affected

No product.

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

CWE-88

Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')

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