Details

The .Net framework can be configured to utilize a different proxy or altogether bypass the default proxy settings in the client’s browser. This may lead to the framework using a proxy that is not approved for use. If the proxy is malicious, this could lead to a loss of application integrity and confidentiality.

Solution

Open Windows explorer and search for all ‘*.exe.config’ and ‘machine.config’ files.

Search each file for the ‘defaultProxy’ element.

Clear the values contained in the ‘defaultProxy’ element, and the ‘bypasslist’, ‘module’, and ‘proxy’ child elements.

The IAO must provide documented approvals of any non-default proxy servers.

Supportive Information

The following resource is also helpful.

• https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_MS_DotNet_Framework_4-0_V2R1_STIG.ziphttps://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_MS_DotNet_Framework_4-0_V2R1_STIG.zip

This security hardening control applies to the following category of controls within NIST 800-53: Configuration Management.This control applies to the following type of system Windows.

References

• 800-53|CM-6b.
• CAT|III
• CCI|CCI-000366
• Rule-ID|SV-225234r615940_rule
• STIG-ID|APPNET0066
• STIG-Legacy|SV-41014
• STIG-Legacy|V-30972
• Vuln-ID|V-225234

Source

• Tenable.com/audits