RUSTSEC-2026-0255
Panic-safety unsoundness in `Chunk`, `RingBuffer`, and `InlineArray` (use-after-free / double-free)
Several methods in sized-chunks drop elements before updating the length/boundary metadata. If an element's Drop panics during the drop, the metadata update is skipped, so the container still treats the already-dropped elements as live. When the container's own Drop runs, those elements are visited again — a use-after-free / double-free reachable from safe Rust.
The RingBuffer methods require the ringbuffer feature. This is distinct from RUSTSEC-2020-0041 (Chunk::clone / insert_from, fixed in 0.6.3); the methods here are still affected in 0.7.0. The repository is archived with issues/PRs disabled and no fix available.
Impact
- CWE-415 (Double Free): the same allocation is freed twice.
- CWE-416 (Use-After-Free): a freed allocation is accessed during a repeated
Drop.
Reachable entirely from safe Rust via catch_unwind with element types whose Drop can panic.
What each source reports
OSV No score
Panic-safety unsoundness in `Chunk`, `RingBuffer`, and `InlineArray` (use-after-free / double-free)
Several methods in sized-chunks drop elements before updating the length/boundary metadata. If an element's Drop panics during the drop, the metadata update is skipped, so the container still treats the already-dropped elements as live. When the container's own Drop runs, those elements are visited again — a use-after-free / double-free reachable from safe Rust.
The RingBuffer methods require the ringbuffer feature. This is distinct from RUSTSEC-2020-0041 (Chunk::clone / insert_from, fixed in 0.6.3); the methods here are still affected in 0.7.0. The repository is archived with issues/PRs disabled and no fix available.
Impact
- CWE-415 (Double Free): the same allocation is freed twice.
- CWE-416 (Use-After-Free): a freed allocation is accessed during a repeated
Drop.
Reachable entirely from safe Rust via catch_unwind with element types whose Drop can panic.
- Record
RUSTSEC-2026-0255- Updated
- 2026-11-02
Affected packages
| Package | Affected | Fixed |
|---|---|---|
sized-chunkscrates.io |
0.0.0-0 and later | None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
RUSTSEC-2026-0255 is a vulnerability with no CVSS score yet in sized-chunks, published August 11, 2026. No source lists public exploit code. No source names a fixed version.