CVE-2026-53791 (GCVE-0-2026-53791)

Vulnerability from cvelistv5 – Published: 2026-08-13 14:38 – Updated: 2026-08-14 18:09
VLAI
Title
rsync < 3.5.0 Daemon IP Spoofing via PROXY Protocol Header
Summary
rsync daemon before 3.5.0 contains an IP address spoofing vulnerability that allows unauthenticated remote attackers to bypass IP-based access controls by sending a crafted PROXY protocol header with a forged source address. Attackers who can connect directly to the rsync daemon can inject a spoofed source IP in the PROXY protocol header to circumvent hosts allow/deny rules, gaining unauthorized access that would otherwise be blocked based on their real source address.
Severity
9.1 (Critical)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-14 18:02 UTC
CWE
  • CWE-290 - Authentication Bypass by Spoofing
Assigner
References
Impacted products
Vendor Product Version
RsyncProject rsync Affected: 0 , ≤ 3.4.4 (semver)
Unaffected: 3.5.0 (semver)
Create a notification for this product.
Date Public
2026-08-12 00:00
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.

Sightings

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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.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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Detection rules are retrieved from Rulezet.