Full Report
Chris Eng over [at the Veracode blog] documents how he approached, and decoded the info behind the [2009 Verizon Data Breach Investigations Report ] Its an interesting read, and although in the end it turned out to be just a [Vigenère cipher] and fell to (effectively) a [known plaintext attack], its def. worth the few minutes it will take to read..
Analysis Summary
# Tool/Technique: Vigenère Cipher (as used in the 2009 Verizon DBIR Cover)
## Overview
The Vigenère cipher is a method of encrypting alphabetic text by using a series of interwoven Caesar ciphers based on the letters of a keyword. In the context of the article, it was the encryption mechanism used (intentionally or otherwise) on the cover of the 2009 Verizon Data Breach Investigations Report (DBIR) that Chris Eng successfully decoded.
## Technical Details
- Type: Technique (Cryptography/Encoding)
- Platform: Not applicable (Theoretical/Mathematical cipher, utilized on the report cover)
- Capabilities: Provides polyalphabetic substitution encryption, making frequency analysis more difficult than a simple Caesar cipher.
- First Seen: 16th Century, but contextually relevant to 2009 DBIR cover analysis.
## MITRE ATT&CK Mapping
Since this involves an encryption technique that was potentially used for data hiding or steganography (on the report cover), the closest mapping relates to encoding/decoding information related to the attack itself, rather than direct malicious payload execution.
- **TA0001 - Initial Access** (If used to hide initial payload instructions, though here it was cover text)
- **T1027 - Obfuscated Files or Information**
- **T1027.003 - Steganography** (Contextually related to hiding data within seemingly innocuous media, like a document cover)
## Functionality
### Core Capabilities
- Encryption of plaintext into ciphertext using a keyword.
- Relies on a polyalphabetic substitution table (Vigenère square).
### Advanced Features
- Effective resistance against basic frequency analysis due to the use of multiple Caesar shifts determined by the key. The article notes its weakness against a known-plaintext attack renders it ineffective against knowledgeable adversaries.
## Indicators of Compromise
- File Hashes: N/A (The artifact is the composition/text on the 2009 DBIR cover)
- File Names: N/A
- Registry Keys: N/A
- Network Indicators: N/A
- Behavioral Indicators: N/A
## Associated Threat Actors
- Haroon Meer and Chris Eng (Analysts who reversed the cipher). The original source of the cipher (if intended as protection for DBIR summary data) is not specified beyond the Verizon DBIR context.
## Detection Methods
- Signature-based detection: Not applicable for a mathematical cipher.
- Behavioral detection: Not applicable.
- YARA rules if available: N/A
## Mitigation Strategies
- **Prevention:** Using modern, cryptographically strong encryption algorithms (e.g., AES, RSA) instead of classical ciphers for sensitive data protection.
- **Hardening:** Ensuring that any text or metadata intended to be hidden or protected is secured using established cryptographic primitives, not historical ciphers susceptible to known-plaintext analysis.
## Related Tools/Techniques
- Caesar Cipher (Simpler substitution cipher)
- One-Time Pad (The theoretically unbreakable cipher)
- Known-plaintext attack (The method used to break this specific instance)