RUSTSEC-2026-0258: h2 unbounded empty DATA frames

> h2 unbounded empty DATA frames

| Details | |
| ------------------- | ---------------------------------------------- |
| Package | `h2` |
| Version | `0.4.13` |
| URL | [https://github.com/hyperium/hyper/security/advisories/GHSA-q83h-524g-xf6h](https://github.com/hyperium/hyper/security/advisories/GHSA-q83h-524g-xf6h) |
| Date | 2026-08-17 |
| Patched versions | `>=0.4.16` |

The h2 crate, used internally by hyper, had a flaw that would accept and queue empty DATA frames without limit.
If streams were not actively drained, this could lead to unbounded memory usage, or a panic if the length overflows.

Low severity.

Patched in v0.4.16.

See [advisory page](https://rustsec.org/advisories/RUSTSEC-2026-0258.html) for additional details.

Start by inspecting the Cargo manifests and dependency resolution for h2, which is used internally by hyper. Update the resolved h2 dependency to version 0.4.16 or later, then verify that the dependency is no longer pinned to 0.4.13 and that the project checks pass.

Written by the indexing model from the issue text.