Server-Side Request Forgery (trace.axd)

Summary #

Netsparker detected a Server-Side Request Forgery based on pattern matching and confirmed the vulnerability using specific trace.axd related requests.

Impact #

Server-Side Request Forgery allows an attacker to make local and/or remote network requests while masquerading as the target server.

Having trace.axd endpoint that is accessible through SSRF leads to attacker gaining access to request details and server variables of all sessions, among other information.

Remediation #

Where possible, do not use users' input for URLs.
If you definitely need dynamic URLs, use whitelisting. Make a list of valid, accepted URLs and do not accept other URLs.
Ensure that you only accept URLs those are located on the trusted domains.

In addition to above, apply the following changes on your web.config file to disable ASP.NET tracing:

<System.Web>
     <trace enabled="false" />
</System.Web>

Classifications #

PCI v3.1-6.5.6; PCI v3.2-6.5.6; CAPEC-347; CWE-918; HIPAA-164.306(a), 164.308(a); ISO27001-A.14.2.5; WASC-15; OWASP 2013-A5; OWASP 2017-A6 , CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:H/RL:O/RC:C

Netsparker Security Insights #