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Vulnerability DatabaseCVE-2021-22958

CVE-2021-22958: 
PHP vulnerability analysis and mitigation

Overview

A Server-Side Request Forgery (SSRF) vulnerability was discovered in concrete5 versions prior to 8.5.5. The vulnerability allowed attackers to bypass localhost restrictions by using decimal notation encoded IP addresses, enabling interaction with local services (CVE Details, NVD).

Technical details

The vulnerability is classified as CWE-918 (Server-Side Request Forgery). It received a CVSS v3.1 Base Score of 9.8 (CRITICAL) with the vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. The vulnerability specifically involved the ability to bypass IP address restrictions through decimal notation encoding, which could allow access to localhost and internal network services (NVD).

Impact

The impact of this vulnerability varies depending on the services exposed locally. It could potentially allow attackers to interact with internal services and access sensitive information that should normally be restricted (CVE Details).

Mitigation and workarounds

The vulnerability was fixed in concrete5 version 8.5.5. Users are advised to upgrade to this version or later to address the SSRF vulnerability (Release Notes).

Additional resources

Source: This report was generated using AI

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