DuckDB is a SQL database management system. DuckDB implemented block-based encryption of DB on the filesystem starting with DuckDB 1.4.0. There are a few issues related to this implementation. The DuckDB can fall back to an insecure random number generator (pcg32) to generate cryptographic keys or IVs. When clearing keys from memory, the compiler may remove the memset() and leave sensitive data on the heap. By modifying the database header, an attacker could downgrade the encryption mode from GCM to CTR to bypass integrity checks. There may be a failure to check return value on call to OpenSSL rand_bytes(). An attacker could use public IVs to compromise the internal state of RNG and determine the randomly generated key used to encrypt temporary files, get access to cryptographic keys if they have access to process memory (e.g. through memory leak),circumvent GCM integrity checks, and/or influence the OpenSSL random number generator and DuckDB would not be able to detect a failure of the generator. Version 1.4.2 has disabled the insecure random number generator by no longer using the fallback to write to or create databases. Instead, DuckDB will now attempt to install and load the OpenSSL implementation in the httpfs extension. DuckDB now uses secure MbedTLS primitive to clear memory as recommended and requires explicit specification of ciphers without integrity checks like CTR on ATTACH. Additionally, DuckDB now checks the return code.
The product uses a broken or risky cryptographic algorithm or protocol.
Cryptographic algorithms are the methods by which data is scrambled to prevent observation or influence by unauthorized actors. Insecure cryptography can be exploited to expose sensitive information, modify data in unexpected ways, spoof identities of other users or devices, or other impacts. It is very difficult to produce a secure algorithm, and even high-profile algorithms by accomplished cryptographic experts have been broken. Well-known techniques exist to break or weaken various kinds of cryptography. Accordingly, there are a small number of well-understood and heavily studied algorithms that should be used by most products. Using a non-standard or known-insecure algorithm is dangerous because a determined adversary may be able to break the algorithm and compromise whatever data has been protected. Since the state of cryptography advances so rapidly, it is common for an algorithm to be considered “unsafe” even if it was once thought to be strong. This can happen when new attacks are discovered, or if computing power increases so much that the cryptographic algorithm no longer provides the amount of protection that was originally thought. For a number of reasons, this weakness is even more challenging to manage with hardware deployment of cryptographic algorithms as opposed to software implementation. First, if a flaw is discovered with hardware-implemented cryptography, the flaw cannot be fixed in most cases without a recall of the product, because hardware is not easily replaceable like software. Second, because the hardware product is expected to work for years, the adversary’s computing power will only increase over time.