Tag Archives: CWE- 807

CWE-807 – Reliance on Untrusted Inputs in a Security Decision

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Description

The application uses a protection mechanism that relies on the existence or values of an input, but the input can be modified by an untrusted actor in a way that bypasses the protection mechanism.

Modes of Introduction:

– Architecture and Design

Likelihood of Exploit: High

 

Related Weaknesses

CWE-693

 

Consequences

Confidentiality, Access Control, Availability, Other: Bypass Protection Mechanism, Gain Privileges or Assume Identity, Varies by Context

Attackers can bypass the security decision to access whatever is being protected. The consequences will depend on the associated functionality, but they can range from granting additional privileges to untrusted users to bypassing important security checks. Ultimately, this weakness may lead to exposure or modification of sensitive data, system crash, or execution of arbitrary code.

 

Potential Mitigations

Phase: Architecture and Design

Effectiveness:

Description: 

Phase: Architecture and Design

Effectiveness:

Description: 

Phase: Architecture and Design

Effectiveness:

Description: 

For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

Phase: Operation, Implementation

Effectiveness:

Description: 

When using PHP, configure the application so that it does not use register_globals. During implementation, develop the application so that it does not rely on this feature, but be wary of implementing a register_globals emulation that is subject to weaknesses such as CWE-95, CWE-621, and similar issues.

Phase: Architecture and Design, Implementation

Effectiveness:

Description: 

CVE References

 

  • CVE-2009-1549
    • Attacker can bypass authentication by setting a cookie to a specific value.
  • CVE-2009-1619
    • Attacker can bypass authentication and gain admin privileges by setting an “admin” cookie to 1.
  • CVE-2009-0864
    • Content management system allows admin privileges by setting a “login” cookie to “OK.”
  • CVE-2008-5784
    • e-dating application allows admin privileges by setting the admin cookie to 1.
  • CVE-2008-6291
    • Web-based email list manager allows attackers to gain admin privileges by setting a login cookie to “admin.”