CVE-2021-4226

RSFirewall < 1.1.25 - IP Block Bypass

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Published Dec 15, 2022 CVSS 3.1 · 9.8 Critical EPSS < 1% KEV · Not listed

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.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Unknown

RSFirewall!

unaffected

Version	Status	Constraints
`0`	affected	< 1.1.25

Configuration 1 [-]

cpe:2.3:a:rsjoomla:rsfirewall\!:*:*:*:*:*:wordpress:*:*

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source	ID	Title
EUVD	EUVD-2021-34084	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.

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.546% probability within 30 days)

Exploitation poc

Automatable yes

Technical Impact total

References

Link	Providers
https://wpscan.com/vulnerability/c0ed80c8-ebbf-4ed9-b02f-31660097c352

History

May 27, 2025 9:30 PM Weaknesses updated View changes

Type	Values Removed	Values Added
Weaknesses		NVD-CWE-noinfo

Apr 21, 2025 3:15 PM Weaknesses updated. Scoring metrics updated View changes

Type	Values Removed	Values Added
Weaknesses		CWE-345
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Subscriptions

Rsjoomla Rsfirewall\!

Weaknesses

Sources

CVE record Updated: Apr 21, 2025, 2:18 PM

Status: PUBLISHED
Assigner: WPScan
Published: Dec 15, 2022, 5:14 PM
Updated: Apr 21, 2025, 2:18 PM
Reserved: Apr 10, 2022, 6:55 AM

View source JSON

Vulnrichment Updated: Aug 3, 2024, 5:16 PM

Updated: Aug 3, 2024, 5:16 PM

NVD Updated: Jun 17, 2026, 4:19 AM

Status: Analyzed
Published: Dec 15, 2022, 7:15 PM
Modified: Jun 17, 2026, 4:19 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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