GHSA-2jq9-6xx7-3h29 Use of uninitialized memory in temporary

Not scored Published 22 Aug 2018

Use of uninitialized memory for RNG seeding in a testing library causes undefined behavior, potentially leading to unpredictable results or crashes.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Not stated
Victim action needed: Not needed
Fix: Available

What is GHSA-2jq9-6xx7-3h29?

GHSA-2jq9-6xx7-3h29 is a memory corruption vulnerability in temporary, published on 22 Aug 2018.

Official description

Uninit memory is used as a RNG seed in temporary

The following function is used as a way to get entropy from the system, which does operations on and exposes uninit memory, which is UB.

fn random_seed(_: &amp;Path, _: &amp;str) -&gt; [u64; 2] {
    use std::mem::uninitialized as rand;
    unsafe { [rand::&lt;u64&gt;() ^ 0x12345678, rand::&lt;u64&gt;() ^ 0x87654321] }
}

This has been resolved in the 0.6.4 release.

The crate is not intended to be used outside of a testing environment.

For a general purpose crate to create temporary directories, tempfile is an alternative for this crate.

Which versions are affected by GHSA-2jq9-6xx7-3h29?

3 open source packages ship an affected version, including temporary.

Package	Affected	Fixed in
`temporary` crates.io	From `0.3.0`	`0.6.4`
`temporary` crates.io	From `0.3.0`	`0.6.4`
`temporary` crates.io	From `0.3.0`	`0.6.4`

How do I fix GHSA-2jq9-6xx7-3h29?

Upgrade temporary to 0.6.4 or later.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is GHSA-2jq9-6xx7-3h29 being exploited?

There is no known exploitation of GHSA-2jq9-6xx7-3h29 in the wild and no public exploit code.

Sources

Also known as RUSTSEC-2018-0022.