CVE-2021-45338
Multiple privilege escalation vulnerabilities in Avast Antivirus prior to 20.4 allow a local user...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
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.
- Record
CVE-2021-45338- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.2 High
AV:L/AC:L/Au:N/C:C/I:C/A:C - Updated
- 2026-11-02
CVE List No score
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.
- Record
CVE-2021-45338- Updated
- 2026-11-02
EUVDEUVD-2021-32111 No score
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.
- Record
EUVD-2021-32111- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-9v35-rf4g-xvc2
Multiple privilege escalation vulnerabilities in Avast Antivirus prior to 20.4 allow a local user...
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.
- Record
GHSA-9v35-rf4g-xvc2- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-269
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-45338 is a high vulnerability (CVSS 7.8) in Avast Antivirus, published December 27, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.39%, the 33rd percentile. No source names a fixed version.
References
avast.com/hacker-hall-of-fame/en/researcher-david-eade-reports-antitrack-bug-to-avast-0
github.com/the-deniss/Vulnerability-Disclosures/tree/main/CVE-2021-AVST1.1
nvd.nist.gov/vuln/detail/CVE-2021-45338