# CVE-2021-34413: Race condition in Zoom Plugin for Microsoft Outlook for MacOS

> A race condition in the Zoom Outlook plugin for macOS allows local attackers to execute malicious code with elevated privileges during installation.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 27 Sep 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-mgjc-79v8-mc48

## What is CVE-2021-34413?

CVE-2021-34413 is a high-severity vulnerability in Zoom Plugin for Microsoft Outlook for MacOS, published on 27 Sep 2021. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

All versions of the Zoom Plugin for Microsoft Outlook for MacOS before 5.3.52553.0918 contain a Time-of-check Time-of-use (TOC/TOU) vulnerability during the plugin installation process. This could allow a standard user to write their own malicious application to the plugin directory, allowing the malicious application to execute in a privileged context.

Weakness: CWE-367 (Time-of-check Time-of-use (TOCTOU) Race Condition)

## Which versions are affected by CVE-2021-34413?

It affects 1 product.


Products: Zoom Zoom Plugin for Microsoft Outlook.

## How do I fix CVE-2021-34413?

No fix has been published for CVE-2021-34413 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-34413 being exploited?

There is no known exploitation of CVE-2021-34413 in the wild and no public exploit code.

## Other vulnerabilities in Zoom Plugin for Microsoft Outlook for MacOS

- [CVE-2021-34410](https://insights.sbomify.com/CVE-2021-34410/): Privilege escalation in Zoom Plugin for Microsoft Outlook for Mac (high 7.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-34413 and fix it if it is affected.

What it is: CVE-2021-34413 is a high-severity vulnerability in Zoom Plugin for Microsoft Outlook for MacOS, published on 27 Sep 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-34413 in the wild and no public exploit code.

Affected product: Zoom Plugin for Microsoft Outlook for MacOS. No package-level version data is available, so check the vendor advisory linked from the reference page.

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/CVE-2021-34413/ (Markdown: https://insights.sbomify.com/CVE-2021-34413/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-34413
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-34413
- OSV: https://osv.dev/vulnerability/CVE-2021-34413

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-34413/
Summaries are generated and may contain mistakes; the official description above is the record.