Affected versions of this crate would call Vec::set_len on an uninitialized vector with user-provided type parameter, in an interface of the HDR image format decoder. They would then also call other code that could panic before initializing all instances.

This could run Drop implementations on uninitialized types, equivalent to use-after-free, and allow an attacker arbitrary code execution.

Two different fixes were applied. It is possible to conserve the interface by ensuring proper initialization before calling Vec::set_len. Drop is no longer called in case of panic, though.

Starting from version 0.22, a breaking change to the interface requires callers to pre-allocate the output buffer and pass a mutable slice instead, avoiding all unsafe code.

In the affected version of this crate, the result of the race condition is that one or more tasks in the worker queue can be popped twice instead of other tasks that are forgotten and never popped. If tasks are allocated on the heap, this can cause double free and a memory leak. If not, this still can cause a logical bug.

Crates using Stealer::steal, Stealer::steal_batch, or Stealer::steal_batch_and_pop are affected by this issue.

Credits to @kmaork for discovering, reporting and fixing the bug.