RUSTSEC-2026-0272: Panic-safety unsoundness in `Stack::pop`, `Fifo::pop_front` and `Value::replace_stable` (use-after-free / double-free)

What to do

1. See which version you have: cargo tree -i stack_dst (it also shows which of your dependencies pulls it in).
2. Update within your version requirement: cargo update -p stack_dst. If the fix is a newer major or minor than your requirement allows, raise it in Cargo.toml (for example stack_dst = "0.8.2") or update the dependency that pulls it in.
3. Check again with cargo audit, or paste your Cargo.lock into our Cargo.toml checker.

Details from the advisory

Three removal and replacement paths destroy an initialized value before committing the metadata change that removes it. Destruction runs T::drop(), which is user code and may panic. If it does, the commit is skipped and the container still claims ownership of the already-destroyed value, so its own destructor drops that value a second time.

Stack::pop drops the top value before reducing next_ofs. Stack's destructor pops in a loop, so an unchanged next_ofs re-drops the same value.

Fifo::pop_front (via pop_front_inner) drops the front value before advancing read_pos. An unchanged read_pos still points at the destroyed value.

Value::replace_stable drops the existing value before writing the replacement. If the destructor panics the replacement is never written, but the backing storage still holds the old value's metadata.

This is separate from RUSTSEC-2021-0033, which covered a clone panic on insertion in push_cloned and was fixed in 0.6.1.

Impact

A heap-owning value is freed twice, corrupting the allocator. Reachable from safe Rust with any element type whose Drop can panic , no unsafe on the caller's side.

• CWE-415 (Double Free)
• CWE-416 (Use-After-Free)

Confirmed under AddressSanitizer, which reports attempting double-free on all three paths.

Fix

Fixed in 0.8.2.

References

• Package: crates.io/crates/stack_dst
• Advisory: rustsec.org/advisories/RUSTSEC-2026-0272.html
• Report: github.com/thepowersgang/stack_dst-rs/issues/16

From the RustSec Advisory Database (CC0-1.0) via the OSV export, downloaded Oct 24, 2026. Severity score computed from the published CVSS vector.

Other advisories for stack_dst

• Vulnerability CriticalRUSTSEC-2021-0033 · 2021-02-22push_cloned can drop uninitialized memory or double free on panic

Full security history of stack_dst