{"id":"RUSTSEC-2026-0255","title":"Panic-safety unsoundness in `Chunk`, `RingBuffer`, and `InlineArray` (use-after-free / double-free)","summary":"Panic-safety unsoundness in `Chunk`, `RingBuffer`, and `InlineArray` (use-after-free / double-free)","severity":"none","vendor":"sized-chunks","product":"sized-chunks","ecosystem":"rust","affected":["sized-chunks >= 0.0.0-0"],"published":"2026-08-11","updated":"2026-08-12","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/RUSTSEC-2026-0255","references":[{"url":"https://crates.io/crates/sized-chunks"},{"url":"https://rustsec.org/advisories/RUSTSEC-2026-0255.html"}],"tags":["osv","rust"],"ingestedAt":"2026-08-12T19:18:08.973Z","slug":"RUSTSEC-2026-0255","body":"## Overview\n\nSeveral 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.\n\n## Affected packages\n\n- `sized-chunks >= 0.0.0-0`\n\n## Remediation\n\nRefer to the advisory for the patched release.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}