CVE-2026-6676: CWE-787 Out-of-bounds Write in Gen Digital Avira Antivirus
Heap buffer out-of-bounds write vulnerability in Avira Antivirus engine when scanning a malformed POSIX tar archive may allow Local Execution of Code or Denial-of-Service of the antivirus engine process. This issue affects Avira Antivirus on Windows, macOS, and Linux for engine builds before 8.3.27.12.
AI Analysis
Technical Summary
CVE-2026-6676 is a heap buffer out-of-bounds write vulnerability in the Avira Antivirus engine triggered by scanning a malformed POSIX tar archive. This vulnerability can lead to local code execution or denial-of-service against the antivirus engine process. It affects Avira Antivirus engine versions before 8.3.27.12 on Windows, macOS, and Linux. The CVSS 3.1 base score is 7.8, indicating high severity, with attack vector local, low attack complexity, no privileges required, user interaction required, and high impact on confidentiality, integrity, and availability.
Potential Impact
Successful exploitation can result in local execution of arbitrary code or denial-of-service of the antivirus engine process, potentially compromising system security and stability on affected platforms.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, avoid scanning untrusted or malformed POSIX tar archives locally to reduce risk.
CVE-2026-6676: CWE-787 Out-of-bounds Write in Gen Digital Avira Antivirus
Description
Heap buffer out-of-bounds write vulnerability in Avira Antivirus engine when scanning a malformed POSIX tar archive may allow Local Execution of Code or Denial-of-Service of the antivirus engine process. This issue affects Avira Antivirus on Windows, macOS, and Linux for engine builds before 8.3.27.12.
CVSS v3.1
Score 7.8high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-6676 is a heap buffer out-of-bounds write vulnerability in the Avira Antivirus engine triggered by scanning a malformed POSIX tar archive. This vulnerability can lead to local code execution or denial-of-service against the antivirus engine process. It affects Avira Antivirus engine versions before 8.3.27.12 on Windows, macOS, and Linux. The CVSS 3.1 base score is 7.8, indicating high severity, with attack vector local, low attack complexity, no privileges required, user interaction required, and high impact on confidentiality, integrity, and availability.
Potential Impact
Successful exploitation can result in local execution of arbitrary code or denial-of-service of the antivirus engine process, potentially compromising system security and stability on affected platforms.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, avoid scanning untrusted or malformed POSIX tar archives locally to reduce risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GEN
- Date Reserved
- 2026-04-20T14:46:06.355Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a2c8e3ee617e2d834d0f248
Added to database: 06/12/2026, 22:54:54 UTC
Last enriched: 06/20/2026, 16:02:01 UTC
Last updated: 07/31/2026, 19:23:00 UTC
Views: 90
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
External Links
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.