Reported

September 4, 2026

Issued

September 21, 2026

Package

imbl-sized-chunks (crates.io)

Type

Vulnerability

Categories

• memory-corruption

Keywords

#memory-safety #double-free #use-after-free #panic-safety

References

• https://github.com/jneem/imbl-sized-chunks/pull/14

Patched

• >=0.2.0

Affected Functions

Version

imbl_sized_chunks::inline_array::InlineArray::clear

• <0.2.0

imbl_sized_chunks::inline_array::InlineArray::truncate

• <0.2.0

imbl_sized_chunks::sized_chunk::Chunk::clear

• <0.2.0

imbl_sized_chunks::sized_chunk::Chunk::drop_left

• <0.2.0

imbl_sized_chunks::sized_chunk::Chunk::drop_right

• <0.2.0

Description

Chunk::{clear, drop_left, drop_right} and InlineArray::{clear, truncate} drop the removed elements before updating the metadata that records which slots hold live values — the left/right index pair for Chunk, the length field for InlineArray. If an element's Drop panics during the drop, that update is never reached, so the collection still treats the already-dropped elements as live. When the collection is later dropped (its destructor walks the range described by the stale metadata), or a subsequent operation touches the same slots, those elements are dropped a second time — a double free (CWE-415) / use-after-free (CWE-416) reachable from safe Rust.

The stale field is left and right for Chunk::clear, left for drop_left, right for drop_right, and the length field for both InlineArray methods.

Mitigation

Upgrade to imbl-sized-chunks 0.2.0 or later, which commits the metadata before dropping any element (fixed in jneem/imbl-sized-chunks#14, released in 0.2.0).

Advisory available under CC0-1.0 license.