Issue name

Referer-dependent response

Typical severity

Information

Issue description

Application responses may depend systematically on the presence or absence of the Referer header in requests. This behavior does not necessarily constitute a security vulnerability, and you should investigate the nature of and reason for the differential responses to determine whether a vulnerability is present.

Common explanations for Referer-dependent responses include:

Issue remediation

The Referer header is not a robust foundation on which to build access controls. Any such measures should be replaced with more secure alternatives that are not vulnerable to Referer spoofing.

If the contents of responses is updated based on Referer data, then the same defenses against malicious input should be employed here as for any other kinds of user-supplied data.

References

Vulnerability classifications