# OSV-2021-1629: Heap-buffer-overflow in Curl_sasl_decode_mech

> A heap-buffer-overflow in cURL's SASL mechanism decoding can lead to crashes or potential code execution when processing malicious URLs.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not stated
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 27 Nov 2021

## What is OSV-2021-1629?

OSV-2021-1629 is a memory corruption vulnerability in curl, published on 27 Nov 2021. It can be exploited over the network, with no action from the victim.

### Official description

OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=41403

```
Crash type: Heap-buffer-overflow READ 10
Crash state:
Curl_sasl_decode_mech
Curl_sasl_parse_url_auth_option
smtp_parse_url_options
```

## Which versions are affected by OSV-2021-1629?

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


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

## How do I fix OSV-2021-1629?

No fix has been published for OSV-2021-1629 yet. Limit exposure of the affected software until one is available.

## Is OSV-2021-1629 being exploited?

There is no known exploitation of OSV-2021-1629 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for OSV-2021-1629 and fix it if it is affected.

What it is: OSV-2021-1629 is a memory corruption vulnerability in curl, published on 27 Nov 2021. It can be exploited over the network, with no action from the victim.
Exploitation: There is no known exploitation of OSV-2021-1629 in the wild and no public exploit code.

Affected packages and fixed versions:
- curl (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-2021-1629/ (Markdown: https://insights.sbomify.com/OSV-2021-1629/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/OSV-2021-1629

---
From sbomify Insights: https://insights.sbomify.com/OSV-2021-1629/
Summaries are generated and may contain mistakes; the official description above is the record.