CWE-329: Generation of Predictable IV with CBC Mode

ID CWE-329

Abstraction Variant

Structure Simple

Status Draft

Number of CVEs 5

The product generates and uses a predictable initialization Vector (IV) with Cipher Block Chaining (CBC) Mode, which causes algorithms to be susceptible to dictionary attacks when they are encrypted under the same key.

CBC mode eliminates a weakness of Electronic Code Book (ECB) mode by allowing identical plaintext blocks to be encrypted to different ciphertext blocks. This is possible by the XOR-ing of an IV with the initial plaintext block so that every plaintext block in the chain is XOR'd with a different value before encryption. If IVs are reused, then identical plaintexts would be encrypted to identical ciphertexts. However, even if IVs are not identical but are predictable, then they still break the security of CBC mode against Chosen Plaintext Attacks (CPA).

Modes of Introduction

Phase	Note
Implementation	Developers might dismiss the importance of an unpredictable IV and choose an easier implementation to save effort, weakening the scheme in the process.

Applicable Platforms

Type	Class	Name	Prevalence
Language	Not Language-Specific
Technology	ICS/OT

Relationships

View			Weakness
# ID	View	Status	# ID	Name	Abstraction	Structure	Status
CWE-1000	Research Concepts	Draft	CWE-1204	Generation of Weak Initialization Vector (IV)	Base	Simple	Incomplete
CWE-1000	Research Concepts	Draft	CWE-573	Improper Following of Specification by Caller	Class	Simple	Draft

CVEs Published

Based on CVE published date

CVSS Severity

CVSS Severity - By Year

CVSS Base Score

# CVE	Description	CVSS	EPSS	EPSS Trend (30 days)	Affected Products	Weaknesses	Security Advisories	Exploits	PoC	Pubblication Date	Modification Date
# CVE	Description	CVSS	EPSS	EPSS Trend (30 days)	Affected Products	Weaknesses	Security Advisories	PoC	Pubblication Date	Modification Date