A bug in the SmallVec::insert_many method caused it to allocate a buffer that was smaller than needed. It then wrote past the end of the buffer, causing a buffer overflow and memory corruption on the heap.

This bug was only triggered if the iterator passed to insert_many yielded more items than the lower bound returned from its size_hint method.

The flaw was corrected in smallvec 0.6.14 and 1.6.1, by ensuring that additional space is always reserved for each item inserted. The fix also simplified the implementation of insert_many to use less unsafe code, so it is easier to verify its correctness.

Thank you to Yechan Bae (@Qwaz) and the Rust group at Georgia Tech’s SSLab for finding and reporting this bug.

Working with specific payloads can cause a Denial of Service (DoS) vector.

Both Decompress and Compress implementations can enter into infinite loops given specific payloads entered that trigger it.

The issue is described in great detail in the bzip2 repository issue.

Thanks to bjrjk for finding and providing the patch for the issue and the maintainer responsibly responding to release a fix quickly.

Users who use the crate with untrusted data should update the bzip2 to 0.4.4.