Heap Buffer Out-of-Bounds Write in Avira Antivirus Engine
CVE-2026-6676

7.8HIGH

Key Information:

Vendor

Gen Digital

Status
Avira Antivirus
Vendor
CVE Published:
12 June 2026

What is CVE-2026-6676?

A vulnerability exists in the Avira Antivirus engine that could allow heap buffer out-of-bounds write when processing a malformed POSIX tar archive. This flaw may lead to local execution of code, posing a significant risk to the antivirus engine and potentially resulting in a denial-of-service condition. Users with versions prior to 8.3.27.12 on Windows, macOS, and Linux should assess their security posture and consider upgrading to mitigate these risks.

Affected Version(s)

Avira Antivirus Windows 0

References

https://www.gendigital.com/us/en/contact-us/security-advi...

CVSS V3.1

Score:
7.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Local
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Mike Zhang, an independent security researcher
.