CWE-1204
Generation of Weak Initialization Vector (IV)
Description
The product uses a cryptographic primitive that uses an Initialization Vector (IV), but the product does not generate IVs that are sufficiently unpredictable or unique according to the expected cryptographic requirements for that primitive.
By design, some cryptographic primitives (such as block ciphers) require that IVs must have certain properties for the uniqueness and/or unpredictability of an IV. Primitives may vary in how important these properties are. If these properties are not maintained, e.g. by a bug in the code, then the cryptography may be weakened or broken by attacking the IVs themselves.
Parent Weaknesses (ChildOf)
Common Consequences
Scope
Impact
Read Application Data
Potential Mitigations
Different cipher modes have different requirements for their IVs. When choosing and implementing a mode, it is important to understand those requirements in order to keep security guarantees intact. Generally, it is safest to generate a random IV, since it will be both unpredictable and have a very low chance of being non-unique. IVs do not have to be kept secret, so if generating duplicate IVs is a concern, a list of already-used IVs can be kept and checked against. NIST offers recommendations on generation of IVs for modes of which they have approved. These include options for when random IVs are not practical. For CBC, CFB, and OFB, see [REF-1175]; for GCM, see [REF-1178].
CVE-2020-1472ZeroLogon vulnerability - use of a static IV of all zeroes in AES-CFB8 mode
CVE-2011-3389BEAST attack in SSL 3.0 / TLS 1.0. In CBC mode, chained initialization vectors are non-random, allowing decryption of HTTPS traffic using a chosen plaintext attack.
CVE-2001-0161wireless router does not use 6 of the 24 bits for WEP encryption, making it easier for attackers to decrypt traffic
CVE-2001-0160WEP card generates predictable IV values, making it easier for attackers to decrypt traffic
CVE-2017-3225device bootloader uses a zero initialization vector during AES-CBC
CVE-2016-6485crypto framework uses PHP rand function - which is not cryptographically secure - for an initialization vector
CVE-2014-5386encryption routine does not seed the random number generator, causing the same initialization vector to be generated repeatedly
CVE-2020-5408encryption functionality in an authentication framework uses a fixed null IV with CBC mode, allowing attackers to decrypt traffic in applications that use this functionality
CVE-2017-17704messages for a door-unlocking product use a fixed IV in CBC mode, which is the same after each restart
CVE-2017-11133application uses AES in CBC mode, but the pseudo-random secret and IV are generated using math.random, which is not cryptographically strong.
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Applicable Platforms
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