An error as small as a single flipped memory bit is all it takes to expose a private key.
The vulnerability occurs when there are errors during the signature generation that takes place when a client and server are establishing a connection. It affects only keys using the RSA cryptographic algorithm, which the researchers found in roughly a third of the SSH signatures they examined. That translates to roughly 1 billion signatures out of the 3.2 billion signatures examined. Of the roughly 1 billion RSA signatures, about one in a million exposed the private key of the host.
Researchers in China claim to have reached a breakthrough in quantum computing, figuring out how they can break the RSA public-key encryption system using a quantum computer of around the power that will soon be publicly available.
Breaking 2048-bit RSA — in other words finding a method to consistently and quickly discover the secret prime numbers underpinning the algorithm — would be extremely significant. Although the RSA algorithm itself has largely been replaced in consumer-facing protocols, such as Transport Layer Security, it is still widely used in older enterprise and operational technology software and in many code-signing certificates.
A group of Chinese researchers have just published a paper claiming that they can—although they have not yet done so—break 2048-bit RSA. This is something to take seriously. It might not be correct, but it’s not obviously wrong.
Severity: High
The OpenSSL 3.0.4 release introduced a serious bug in the RSA
implementation for X86_64 CPUs supporting the AVX512IFMA instructions.
This issue makes the RSA implementation with 2048 bit private keys
incorrect on such machines and memory corruption will happen during
the computation. As a consequence of the memory corruption an attacker
may be able to trigger a remote code execution on the machine performing
the computation.