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CVE-2021-4226 (GCVE-0-2021-4226)

Vulnerability from cvelistv5 – Published: 2022-12-15 17:14 – Updated: 2025-04-21 14:18
VLAI
Title
RSFirewall < 1.1.25 - IP Block Bypass
Summary
RSFirewall tries to identify the original IP address by looking at different HTTP headers. A bypass is possible due to the way it is implemented.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-04-21 14:17 UTC
CWE
Assigner
References
URL Tags
https://wpscan.com/vulnerability/c0ed80c8-ebbf-4e… exploitvdb-entrytechnical-description
Impacted products
Vendor Product Version CPE status
Unknown RSFirewall! Affected: 0 , < 1.1.25 (custom)
guessed Create a notification for this product.
Credits
Daniel Ruf
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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Nomenclature

  • 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.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


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