CVE-2026-70452

rsync 3.1.0 before 3.5.0 contains an access control bypass vulnerability that allows remote attackers to circumvent hosts deny rules by inducing DNS resolution failures during hostname-based access control evaluation. When a DNS lookup for a hostname-based deny rule fails, the daemon skips the rule rather than defaulting to a deny decision, enabling attackers who can trigger DNS failures to bypass module-level IP access controls and gain unauthorized access to restricted module file trees.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

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-6692-28cx-wpqq
https://www.vulncheck.com/advisories/rsync-access-control-bypass-via-dns-resolution-failure

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-13 15:19

Updated : 2026-09-08 20:28

NVD link : CVE-2026-70452

Mitre link : CVE-2026-70452

CVE.ORG link : CVE-2026-70452

JSON object : View

Products Affected

No product.

CWE

CWE-636

Not Failing Securely ('Failing Open')

CWE-863

Incorrect Authorization

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