Impact

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.

Patches

No patch is yet available, however work is underway to migrate to a fully constant-time implementation.

Workarounds

The only currently available workaround is to avoid using the rsa crate in settings where attackers are able to observe timing information, e.g. local use on a non-compromised computer is fine.

References

This vulnerability was discovered as part of the "Marvin Attack", which revealed several implementations of RSA including OpenSSL had not properly mitigated timing sidechannel attacks.

With versions of the whoami crate >= 0.5.3 and < 1.5.0, calling any of these functions leads to an immediate stack buffer overflow on illumos and Solaris:

• whoami::username
• whoami::realname
• whoami::username_os
• whoami::realname_os

With versions of the whoami crate >= 0.5.3 and < 1.0.1, calling any of the above functions also leads to a stack buffer overflow on these platforms:

• Bitrig
• DragonFlyBSD
• FreeBSD
• NetBSD
• OpenBSD

This occurs because of an incorrect definition of the passwd struct on those platforms.

As a result of this issue, denial of service and data corruption have both been observed in the wild. The issue is possibly exploitable as well.

This vulnerability also affects other Unix platforms that aren't Linux or macOS.

This issue has been addressed in whoami 1.5.0.

For more information, see this GitHub issue.