RustCrypto/RSA is a portable RSA implementation in pure Rust. Due to a non-constant-time implementation, information about the private key is leaked through timing information which is observable over the network. An attacker may be able to use that information to recover the key. There is currently no fix available. As a workaround, avoid using the RSA crate in settings where attackers are able to observe timing information, e.g. local use on a non-compromised computer.
Covert timing channels convey information by modulating some aspect of system behavior over time, so that the program receiving the information can observe system behavior and infer protected information.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Rsa | Rustcrypto | * | * |
| Rust-rsa | Ubuntu | bionic | * |
| Rust-rsa | Ubuntu | trusty | * |
| Rust-rsa | Ubuntu | xenial | * |
In some instances, knowing when data is transmitted between parties can provide a malicious user with privileged information. Also, externally monitoring the timing of operations can potentially reveal sensitive data. For example, a cryptographic operation can expose its internal state if the time it takes to perform the operation varies, based on the state. Covert channels are frequently classified as either storage or timing channels. Some examples of covert timing channels are the system’s paging rate, the time a certain transaction requires to execute, and the time it takes to gain access to a shared bus.