Weakness · High
CWE-827: Improper Control of Document Type Definition
What it is
The product 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 product to expose files, consume excessive system resources, or execute arbitrary http requests on behalf of the attacker.
- Severity (our rating)
- High
- Likelihood of exploit
- Not rated by MITRE
- Introduced during
- Implementation
- Exploited in the wild
- No CVE in CISA's catalog
In more detail
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.
What an attacker can do
- Read Files or Directories (Confidentiality)
- DoS: Resource Consumption (CPU) (Availability)
- DoS: Resource Consumption (Memory) (Availability)
- Execute Unauthorized Code or Commands (Integrity, Confidentiality, Availability, Access Control)
- Gain Privileges or Assume Identity (Integrity, Confidentiality, Availability, Access Control)
How to prevent it
MITRE lists no specific mitigation for this weakness. Treat it like its parent weaknesses below: validate input, keep the design simple and review the code where it could appear.
H2 Security
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Start freeSource: MITRE Common Weakness Enumeration, CWE version 4.19.1. CWE is a trademark of The MITRE Corporation.