RUSTSEC-2022-0063: Multiple vulnerabilities resulting in out-of-bounds writes

What to do

1. See which version you have: cargo tree -i linked_list_allocator (it also shows which of your dependencies pulls it in).
2. Update within your version requirement: cargo update -p linked_list_allocator. If the fix is a newer major or minor than your requirement allows, raise it in Cargo.toml (for example linked_list_allocator = "0.10.2") 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

• The heap initialization methods were missing a minimum size check for the given heap size argument. This could lead to **out-of-bound writes** when a heap was initialized with a size smaller than 3 * size_of::<usize> because of metadata write operations.
• When calling Heap::extend with a size smaller than two usizes (e.g., 16 on x86_64), the size was erroneously rounded up to the minimum size, which could result in an **out-of-bounds write**.
• Calling Heap::extend on an empty heap tried to construct a heap starting at address 0, which is also an **out-of-bounds write**.
• One specific way to trigger this accidentally is to call Heap::new (or a similar constructor) with a heap size that is smaller than two usizes. This was treated as an empty heap as well.
• Calling Heap::extend on a heap whose size is not a multiple of the size of two usizes resulted in unaligned writes. It also left the heap in an unexpected state, which might lead to subsequent issues. We did not find a way to exploit this undefined behavior yet (apart from DoS on platforms that fault on unaligned writes).

References

• Package: crates.io/crates/linked_list_allocator
• Advisory: rustsec.org/advisories/RUSTSEC-2022-0063.html
• Web: github.com/rust-osdev/linked-list-allocator/commit/013b0758643943e8df5b17bbb495460ff47e8bbf

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