CVE-2021-4226 - CVE House
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Status published Unknown CVE-2021-4226

RSFirewall < 1.1.25 - IP Block Bypass

Vulnerability Description

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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • Daniel Ruf

References

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Affected Vendor

Affected Software

RSFirewall!
Vulnerable Versions:
0

Timeline

Official Publish: December 15th, 2022
Last Modified: April 21st, 2025
Added to House: July 21st, 2026

CVSS Vectors

No vector data available

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.