# OSV-2023-13: Heap-buffer-overflow in wc_AesCbcEncrypt

> A heap-buffer-overflow in wolfSSL's AES-CBC encryption allows attackers to cause crashes or potentially execute arbitrary code via crafted input.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 19 Jan 2023

## What is OSV-2023-13?

OSV-2023-13 is a memory corruption vulnerability in wolfssl, published on 19 Jan 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=55161

```
Crash type: Heap-buffer-overflow WRITE 16
Crash state:
wc_AesCbcEncrypt
evpCipherBlock
wolfSSL_EVP_CipherUpdate
```

## Which versions are affected by OSV-2023-13?

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


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `wolfssl` | OSS-Fuzz | All versions | None |

## How do I fix OSV-2023-13?

No fix has been published for OSV-2023-13 yet. Limit exposure of the affected software until one is available.

## Is OSV-2023-13 being exploited?

There is no known exploitation of OSV-2023-13 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for OSV-2023-13 and fix it if it is affected.

What it is: OSV-2023-13 is a memory corruption vulnerability in wolfssl, published on 19 Jan 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of OSV-2023-13 in the wild and no public exploit code.

Affected packages and fixed versions:
- wolfssl (OSS-Fuzz): affected all versions; 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/OSV-2023-13/ (Markdown: https://insights.sbomify.com/OSV-2023-13/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/OSV-2023-13

---
From sbomify Insights: https://insights.sbomify.com/OSV-2023-13/
Summaries are generated and may contain mistakes; the official description above is the record.