CVE-2026-70452 (GCVE-0-2026-70452)

Vulnerability from cvelistv5 – Published: 2026-08-13 14:46 – Updated: 2026-08-14 15:46
VLAI
Title
rsync 3.1.0 < 3.5.0 Access Control Bypass via DNS Resolution Failure
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.
Severity
9.1 (Critical)
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
7.4 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-14 15:46 UTC
CWE
  • CWE-863 - Incorrect Authorization
  • CWE-636 - Not Failing Securely ('Failing Open')
Assigner
References
Impacted products
Vendor Product Version
RsyncProject rsync Affected: 3.1.0 , ≤ 3.4.4 (semver)
Unaffected: 3.5.0 (semver)
Create a notification for this product.
Date Public
2026-08-12 00:00
Credits
buger
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.