Affected: time-rs time

time provides date and time handling in Rust. From 0.3.6 to before 0.3.47, when user-provided input is provided to any type that parses with the RFC 2822 format, a denial of service attack via stack exhaustion is possible. The attack relies on formally deprecated and rarely-used features that are part of the RFC 2822 format used in a malicious manner. Ordinary, non-malicious input will never encounter this scenario. A limit to the depth of recursion was added in v0.3.47. From this version, an error will be returned rather than exhausting the stack.

Affected: crates.io: time

### Impact

When user-provided input is provided to any type that parses with the RFC 2822 format, a denial of service attack via stack exhaustion is possible. The attack relies on formally deprecated and rarely-used features that are part of the RFC 2822 format used in a malicious manner. Ordinary, non-malicious input will never encounter this scenario.

### Patches

A limit to the depth of recursion was added in v0.3.47. From this version, an error will be returned rather than exhausting the stack.

### Workarounds

Limiting the length of user input is the simplest way to avoid stack exhaustion, as the amount of the stack consumed would be at most a factor of the length of the input.

Alternatively, avoiding the format altogether would also ensure that the vulnerability is not encountered. To do this, add

```toml disallowed-types = ["time::format_description::well_known::Rfc2822"] ```

to your `clippy.toml` file. This will trigger the `clippy::disallowed_types` lint, which is warn-by-default and can be explicitly denied.