CVE-2026-6676
Avira antivirus engine heap buffer OOB write when scanning a malformed POSIX tar archive
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.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Avira antivirus engine heap buffer OOB write when scanning a malformed POSIX tar archive
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.
- Record
CVE-2026-6676- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
EUVDEUVD-2026-36631
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.
- Record
EUVD-2026-36631- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-c89p-wq36-89h3
Heap buffer out-of-bounds write vulnerability in Avira Antivirus engine when scanning a malformed...
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.
- Record
GHSA-c89p-wq36-89h3- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-6676- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-6676 is a high vulnerability (CVSS 7.8) in Avira Antivirus, published June 12, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.12%, the 1st percentile. No source names a fixed version.