CVE-2026-70452

Summary

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.

Affected Software

VendorProductVersion RangeStatus
RsyncProjectrsync3.1.0 <= 3.4.4affected
RsyncProjectrsync3.5.0unaffected

Weaknesses

  • CWE-863: CWE-863 Incorrect Authorization
  • CWE-636: CWE-636 Not Failing Securely ('Failing Open')

References