Title

The Request Smuggling filter must be enabled. (Cat II impact)

Discussion

Security scans show Request Smuggling vulnerability on IIS server. The vulnerability allows a remote attacker to perform HTTP request smuggling attack. The vulnerability exists due to the way that HTTP proxies (front-end) and web servers (back-end) that do not strictly adhere to RFC standards handle sequences of HTTP requests received from multiple sources. A remote attacker can send a specially crafted request to a targeted IIS Server, perform HTTP request smuggling attack and modify responses or retrieve information from another user's HTTP session.

Check Content

Open Registry Editor. Navigate to "HKLM\System\CurrentControlSet\Services\HTTP\Parameters" Verify "DisableRequestSmuggling” is set to "1". If REG_DWORD DisableRequestSmuggling is not set to 1, this is a finding.

Fix Text

Navigate to "HKLM\System\CurrentControlSet\Services\HTTP\Parameters". Create REG_DWORD "DisableRequestSmuggling” and set it to "1". Note: This can be performed multiple ways; this is an example.

Additional Identifiers

Rule ID: SV-268325r1025163_rule

Vulnerability ID: V-268325

Group Title: SRG-APP-000141-WSR-000015

Expert Comments

CCIs tied to check.

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