Description
### Impact
Unix-like operating systems may segfault due to dereferencing a dangling pointer in specific circumstances. This requires an environment variable to be set in a different thread than the affected functions. This may occur without the user's knowledge, notably in a third-party library.
### Workarounds
No workarounds are known.
### References
- [time-rs/time#293](https://github.com/time-rs/time/issues/293)
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| crates.io | chrono | >= 0.0.0-0, < 0.4.20 | 0.4.20 | RUSTSEC-2020-0159 |