{"id":"RUSTSEC-2026-0255","summary":"Panic-safety unsoundness in `Chunk`, `RingBuffer`, and `InlineArray` (use-after-free / double-free)","details":"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.\n\nThe `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.\n\n## Impact\n\n- **CWE-415 (Double Free):** the same allocation is freed twice.\n- **CWE-416 (Use-After-Free):** a freed allocation is accessed during a repeated `Drop`.\n\nReachable entirely from safe Rust via `catch_unwind` with element types whose `Drop` can panic.","modified":"2026-08-12T10:30:21.348313270Z","published":"2026-08-11T12:00:00Z","database_specific":{"license":"CC0-1.0"},"references":[{"type":"PACKAGE","url":"https://crates.io/crates/sized-chunks"},{"type":"ADVISORY","url":"https://rustsec.org/advisories/RUSTSEC-2026-0255.html"}],"affected":[{"package":{"name":"sized-chunks","ecosystem":"crates.io","purl":"pkg:cargo/sized-chunks"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0.0.0-0"}]}],"ecosystem_specific":{"affects":{"arch":[],"os":[],"functions":["sized_chunks::Chunk::clear","sized_chunks::Chunk::drop_left","sized_chunks::Chunk::drop_right","sized_chunks::InlineArray::clear","sized_chunks::RingBuffer::clear","sized_chunks::RingBuffer::drop_left","sized_chunks::RingBuffer::drop_right"]},"affected_functions":null},"database_specific":{"source":"https://github.com/rustsec/advisory-db/blob/osv/crates/RUSTSEC-2026-0255.json","categories":["memory-corruption"],"cvss":null,"informational":"unsound"}}],"schema_version":"1.9.0"}