Like many other cybersecurity strategies, modern encryption can have vulnerabilities. Modern encryption keys are long enough that brute-force attacks – trying every possible key until the right one is found – are impractical. A 128-bit key has 2128 possible values: 100 billion computers each testing 10 billion operations per second would take over a billion years to try all of these keys.
Modern cryptographic vulnerabilities typically manifest as a slight weakening of the encryption strength. For example, under certain conditions, a 128-bit key only has the strength of a 118-bit key. While the research that discovers such weaknesses are important in terms of ensuring encryption strength, they are not significant in real-world use, often requiring unrealistic assumptions such as unfettered physical access to a server. Successful attacks on modern strong encryption thus center on unauthorized access to keys.