# RUSTSEC-2026-0295: Memory corruption bug on `ApplyResult` type

> A use-after-free vulnerability in the ApplyResult type allows attackers to cause memory corruption, potentially leading to 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:** Yes
- **Published:** 12 Aug 2026

## What is RUSTSEC-2026-0295?

RUSTSEC-2026-0295 is an use after free vulnerability in z3, published on 12 Aug 2026. 

### Official description

The `ApplyResult` type contains a raw pointer to a C++ memory object and has a derived `Clone` implementation which creates a reference to this object without incrementing the associated reference counter. 

As a result, if an instance of `ApplyResult` is duplicated through `Clone` and both instances are dropped a use-after-free can occur.

## Which versions are affected by RUSTSEC-2026-0295?

1 open source package ship an affected version, including z3.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `z3` | crates.io | From 0.0.0-0 | 0.21.0 |

## How do I fix RUSTSEC-2026-0295?

Upgrade z3 to 0.21.0 or later.

## Is RUSTSEC-2026-0295 being exploited?

There is no known exploitation of RUSTSEC-2026-0295 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for RUSTSEC-2026-0295 and fix it if it is affected.

What it is: RUSTSEC-2026-0295 is an use after free vulnerability in z3, published on 12 Aug 2026. 
Exploitation: There is no known exploitation of RUSTSEC-2026-0295 in the wild and no public exploit code.

Affected packages and fixed versions:
- z3 (crates.io): affected from 0.0.0-0; fixed in 0.21.0

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/RUSTSEC-2026-0295/ (Markdown: https://insights.sbomify.com/RUSTSEC-2026-0295/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/RUSTSEC-2026-0295

---
From sbomify Insights: https://insights.sbomify.com/RUSTSEC-2026-0295/
Summaries are generated and may contain mistakes; the official description above is the record.