TI-2021-20486 Aliases CVE-2021-45335 GHSA-gjmr-rw74-6fvm

Sandbox component in Avast Antivirus prior to 20.4 has an insecure permission which could…

LOW 38CWE-276Published 2021-12-27 · Updated 2024-08-04

Key facts

Attack vector: Local
Privileges required: Low
User interaction: None
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: High · High · High
Fix status: No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

Sandbox component in Avast Antivirus prior to 20.4 has an insecure permission which could be abused by local user to control the outcome of scans, and therefore evade detection or delete arbitrary system files.

Why it matters now

EPSS 0.0039 33rd percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
—	—	all versions	—	No fix listed	CNA

— Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:avast:antivirus::::::::	before 20.4	Vulnerable	Avast

cpe:2.3:a:avast:antivirus:*:*:*:*:*:*:*:* Versions before 20.4 Vulnerable ·Avast

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2021-45335
2026-10-03 Alias added: GHSA-gjmr-rw74-6fvm

References

Exploit 1

https://github.com/the-deniss/Vulnerability-Disclosures/tree/main/CVE-2021-AVST3%20%26%20CVE-2021-AVST4%20%26%20CVE-2021-AVST5

Advisory 1

https://www.avast.com/hacker-hall-of-fame/en/researcher-david-eade-reports-antitrack-bug-to-avast-0

TI-2020-08753 An issue was discovered in Avast Antivirus before 20. CVSS 3.1CRITICAL 9.8
TI-2017-05872 In Avast Antivirus before v17, using the LPC interface API exposed by the AvastSVC.exe… CVSS 3.0CRITICAL 9.8
TI-2025-03074 Integer Overflow in Avast Antiviurs 25.1.981.6 on Windows may result in privilege escalation CVSS 3.1CRITICAL 9.8
TI-2025-11929 Time-of-check time-of-use race condition in Avast Antivirus CVSS 3.1CRITICAL 9.9
TI-2021-20488 Privilege escalation vulnerability in the Self-Defense driver of Avast Antivirus prior to… CVSS 3.1HIGH 8.8
TI-2021-20487 Privilege escalation vulnerability in the Sandbox component of Avast Antivirus prior to… CVSS 3.1HIGH 8.8

See all 31 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences