CWE-409: Improper Handling of Highly Compressed Data (Data Amplification)

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Description

The product does not handle or incorrectly handles a compressed input with a very high compression ratio that produces a large output.

Extended Description

An example of data amplification is a "decompression bomb," a small ZIP file that can produce a large amount of data when it is decompressed.


ThreatScore

Threat Mapped score: 0.0

Industry: Finiancial

Threat priority: Unclassified


Observed Examples (CVEs)

Related Attack Patterns (CAPEC)

N/A


Attack TTPs

N/A

Modes of Introduction

Phase Note
Architecture and Design N/A
Implementation N/A

Common Consequences

Potential Mitigations

Applicable Platforms


Demonstrative Examples

Intro: The DTD and the very brief XML below illustrate what is meant by an XML bomb. The ZERO entity contains one character, the letter A. The choice of entity name ZERO is being used to indicate length equivalent to that exponent on two, that is, the length of ZERO is 2^0. Similarly, ONE refers to ZERO twice, therefore the XML parser will expand ONE to a length of 2, or 2^1. Ultimately, we reach entity THIRTYTWO, which will expand to 2^32 characters in length, or 4 GB, probably consuming far more data than expected.

<?xml version="1.0"?> <!DOCTYPE MaliciousDTD [ <!ENTITY ZERO "A"> <!ENTITY ONE "&ZERO;&ZERO;"> <!ENTITY TWO "&ONE;&ONE;"> ... <!ENTITY THIRTYTWO "&THIRTYONE;&THIRTYONE;"> ]> <data>&THIRTYTWO;</data>

Notes

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