# GHSA-77h3-w9rx-hj3q: User-defined implementations of the safe trait scratchpad::Tracking can cause heap buffer overflows

> A Rust library allows heap buffer overflows via user-defined trait implementations, potentially enabling arbitrary code execution or crashes.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Not stated
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 14 Aug 2025
- **Also known as:** RUSTSEC-2025-0049

## What is GHSA-77h3-w9rx-hj3q?

GHSA-77h3-w9rx-hj3q is a memory corruption vulnerability in scratchpad, published on 14 Aug 2025. 

### Official description

The `get` and `set` methods of the public trait `scratchpad::Tracking` interact with unsafe code regions in the crate, and they influence the computation of addresses returned as raw pointers. However, the trait itself is not marked as unsafe, meaning users may provide custom implementations under the assumption that the crate upholds all safety guarantees.

This becomes problematic because even safe implementations of `get` and `set`-written without using any unsafe code-can still result in ill-formed raw pointers. These pointers may later be dereferenced within safe APIs of the crate (e.g., `marker::MarkerBack::allocate_slice_copy`), potentially leading to arbitrary memory access or heap buffer overflows.

According to the [penultimate commit](https://github.com/okready/scratchpad/commit/957dee1a3902f48600b06910e8e0b1d5ee7dab83), the crate is in maintenance mode awaiting a cleanup that will reduce the area of unsafe code. Note that the last commits to the repository are from 4 years ago.

## Which versions are affected by GHSA-77h3-w9rx-hj3q?

3 open source packages ship an affected version, including scratchpad.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `scratchpad` | crates.io | All versions to 1.3.1 | None |
| `scratchpad` | crates.io | All versions to 1.3.1 | None |
| `scratchpad` | crates.io | From 0.0.0-0 | None |

## How do I fix GHSA-77h3-w9rx-hj3q?

No fix has been published for GHSA-77h3-w9rx-hj3q yet. Limit exposure of the affected software until one is available.

## Is GHSA-77h3-w9rx-hj3q being exploited?

There is no known exploitation of GHSA-77h3-w9rx-hj3q in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-77h3-w9rx-hj3q and fix it if it is affected.

What it is: GHSA-77h3-w9rx-hj3q is a memory corruption vulnerability in scratchpad, published on 14 Aug 2025. 
Exploitation: There is no known exploitation of GHSA-77h3-w9rx-hj3q in the wild and no public exploit code.

Affected packages and fixed versions:
- scratchpad (crates.io): affected all versions up to 1.3.1; no fix listed
- scratchpad (crates.io): affected all versions up to 1.3.1; no fix listed
- scratchpad (crates.io): affected from 0.0.0-0; no fix listed

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/GHSA-77h3-w9rx-hj3q/ (Markdown: https://insights.sbomify.com/GHSA-77h3-w9rx-hj3q/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-77h3-w9rx-hj3q

---
From sbomify Insights: https://insights.sbomify.com/GHSA-77h3-w9rx-hj3q/
Summaries are generated and may contain mistakes; the official description above is the record.