CWE

Improper Enforcement of Behavioral Workflow

ID: 841		Date: (C)2012-05-14   (M)2022-10-10
Type: weakness		Status: INCOMPLETE
Abstraction Type: Base

Description

The software supports a session in which more than one behavior must be performed by an actor, but it does not properly ensure that the actor performs the behaviors in the required sequence.

Extended Description

By performing actions in an unexpected order, or by omitting steps, an attacker could manipulate the business logic of the software or cause it to enter an invalid state. In some cases, this can also expose resultant weaknesses.

For example, a file-sharing protocol might require that an actor perform separate steps to provide a username, then a password, before being able to transfer files. If the file-sharing server accepts a password command followed by a transfer command, without any username being provided, the software might still perform the transfer.

Note that this is different than CWE-696, which focuses on when the software performs actions in the wrong sequence; this entry is closely related, but it is focused on ensuring that the actor performs actions in the correct sequence.

Workflow-related behaviors include:

Steps are performed in the expected order.

Required steps are not omitted.

Steps are not interrupted.

Steps are performed in a timely fashion.

Applicable Platforms
None

Related Attack Patterns

• CAPEC-140
• CAPEC-74

Common Consequences

Scope	Technical Impact	Notes
Other	Alter execution logic	An attacker could cause the software to skip critical steps or perform them in the wrong order, bypassing its intended business logic. This can sometimes have security implications.

Detection Methods
None

Potential Mitigations
None

Relationships

Related CWE	Type	View	Chain
CWE-841 ChildOf CWE-438	Category	CWE-699

Demonstrative Examples   (Details)

1. This code is part of an FTP server and deals with various commands that could be sent by a user. It is intended that a user must successfully login before performing any other action such as retrieving or listing files.

Observed Examples

1. CVE-2011-0348 : Bypass of access/billing restrictions by sending traffic to an unrestricted destination before sending to a restricted destination.
2. CVE-2007-3012 : Attacker can access portions of a restricted page by canceling out of a dialog.
3. CVE-2009-5056 : Ticket-tracking system does not enforce a permission setting.
4. CVE-2004-2164 : Shopping cart does not close a database connection when user restores a previous order, leading to connection exhaustion.
5. CVE-2003-0777 : Chain: product does not properly handle dropped connections, leading to missing NULL terminator (CWE-170) and segmentation fault.
6. CVE-2005-3327 : Chain: Authentication bypass by skipping the first startup step as required by the protocol.
7. CVE-2004-0829 : Chain: File server crashes when sent a "find next" request without an initial "find first."
8. CVE-2010-2620 : FTP server allows remote attackers to bypass authentication by sending (1) LIST, (2) RETR, (3) STOR, or other commands without performing the required login steps first.
9. CVE-2005-3296 : FTP server allows remote attackers to list arbitrary directories as root by running the LIST command before logging in.

For more examples, refer to CVE relations in the bottom box.

White Box Definitions
None

Black Box Definitions
None

Taxynomy Mappings

Taxynomy	Id	Name	Fit
WASC	40	Insufficient Process Validation

References:

1. Jeremiah Grossman .Business Logic Flaws and Yahoo Games. 2006-12-08. Published on October 2007.
2. Jeremiah Grossman .Seven Business Logic Flaws That Put Your Website At Risk. Published on October 2007.
3. WhiteHat Security .Business Logic Flaws.
4. WASC .Insufficient Process Validation.
5. Rafal Los Prajakta Jagdale .Defying Logic: Theory, Design, and Implementation of Complex Systems for Testing Application Logic. Published on 2011.
6. Rafal Los .Real-Life Example of a 'Business Logic Defect' (Screen Shots!). Published on 2011.
7. Viktoria Felmetsger Ludovico Cavedon Christopher Kruegel Giovanni Vigna .Toward Automated Detection of Logic Vulnerabilities in Web Applications. USENIX Security Symposium 2010. Published on August 2010.
8. Faisal Nabi .Designing a Framework Method for Secure Business Application Logic Integrity in e-Commerce Systems. International Journal of Network Security, Vol.12, No.1. Section:'pages 29 - 41'. Published on 2011.