CWE-827: Improper Control of Document Type Definition
Improper Control of Document Type Definition
Weakness ID: 827 (Weakness Base)
Status: Incomplete
Description
Description Summary
The software does not restrict a reference to a Document Type Definition (DTD) to the intended control sphere. This might allow attackers to reference arbitrary DTDs, possibly causing the software to expose files, consume excessive system resources, or execute arbitrary http requests on behalf of the attacker.
Extended Description
As DTDs are processed, they might try to read or include files on the machine performing the parsing. If an attacker is able to control the DTD, then the attacker might be able to specify sensitive resources or requests or provide malicious content.
For example, the SOAP specification prohibits SOAP messages from containing DTDs.
Applicable Platforms
Languages
XML
Architectural Paradigms
Web-based
Common Consequences
Scope
Effect
Confidentiality
Technical Impact: Read files or
directories
If the attacker is able to include a crafted DTD and a default entity
resolver is enabled, the attacker may be able to access arbitrary files
on the system.
The DTD may cause the parser to consume excessive CPU cycles or memory using techniques such as nested or recursive entity references (CWE-776).
Integrity
Confidentiality
Availability
Access Control
Technical Impact: Execute unauthorized code or
commands; Gain privileges / assume
identity
The DTD may include arbitrary HTTP requests that the server may
execute. This could lead to other attacks leveraging the server's trust
relationship with other entities.
Product does not properly reject DTDs in SOAP
messages, which allows remote attackers to read arbitrary files, send HTTP
requests to intranet servers, or cause a denial of service.
Description
