CVE-2020-5274 : Exploit Details and Defense Strategies

In Symfony before versions 5.0.5 and 4.4.5, some properties of the Exception were not properly escaped when the

ErrorHandler

rendered its stack trace. This issue has been patched in symfony/http-foundation versions 4.4.5 and 5.0.5.

Understanding CVE-2020-5274

In this CVE, Symfony versions prior to 5.0.5 and 4.4.5 were affected by a vulnerability related to the display of exceptions in non-debug configurations.

What is CVE-2020-5274?

This CVE pertains to a situation where certain properties of the Exception in Symfony were not correctly escaped when the

ErrorHandler

rendered the stack trace. Additionally, the stack trace was displayed even in non-debug configurations, potentially exposing sensitive information.

The Impact of CVE-2020-5274

The impact of this vulnerability is rated as medium severity with a CVSS base score of 4.6. The confidentiality and integrity impacts are low, and user interaction is required for exploitation.

Technical Details of CVE-2020-5274

In-depth technical information about the vulnerability.

Vulnerability Description

The Exception properties were not properly escaped, leading to potential exposure of sensitive information in non-debug configurations.

Affected Systems and Versions

Affected versions include Symfony versions >= 4.0.0 and < 4.4.5, as well as >= 5.0.0 and < 5.0.5.

Exploitation Mechanism

Attack Complexity: Low
Attack Vector: Network
Privileges Required: Low
User Interaction: Required
Scope: Unchanged
Vector String: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N

Mitigation and Prevention

Best practices to mitigate and prevent the CVE.

Immediate Steps to Take

Update Symfony to versions 4.4.5 or 5.0.5, where the issue has been patched.
Ensure that sensitive information is not exposed in error messages.

Long-Term Security Practices

Regularly update Symfony and its components to the latest versions.
Implement secure coding practices to prevent similar vulnerabilities.

Patching and Updates

Apply patches provided by Symfony promptly to address security vulnerabilities.