RUSTSEC-2026-0255: sized-chunks panic-safety unsoundness (UAF/Double-Free)

Vulnerability Overview Vulnerability ID: RUSTSEC-2026-0255 Vulnerability Title: Panic-safety unsoundness in , , and (use-after-free / double-free) Report Date: August 11, 2026 Publication Date: August 12, 2026 Package: (crates.io) Type: Memory unsafety Category: Memory corruption Keywords: #panic-safety #memory-safety #use-after-free #double-free Affected Scope Affected Functions: - (<0.7.0) - (<0.7.0) - (<0.7.0) - (<0.7.0) - (<0.7.0) - (<0.7.0) - (<0.7.0) Description: - In , certain methods remove elements before updating length/boundary metadata. If the element's implementation panics during removal, the metadata update is skipped, and the container still treats the removed elements as active. When the container's own runs, these elements are accessed again, leading to use-after-free or double-free issues. - methods require the feature. This is distinct from RUSTSEC-2020-0041 ( / , fixed in 0.6.3); here, version 0.7.0 remains affected. The repository has been archived, issues/PRs are disabled, and no fix is available. Impact: - CWE-415 (Double Free): The same allocation is freed twice. - CWE-416 (Use-After-Free): Accessing a freed allocation during repeated calls. - Fully reachable from safe Rust via , provided the element type's can panic. Remediation Fixed Version: No fixed version available. Recommendation: Since the repository has been archived and no fix is available, users are advised to avoid using the affected versions and consider migrating to other well-maintained libraries.

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RUSTSEC-2026-0255: sized-chunks panic-safety unsoundness (UAF/Double-Free)