Vulnerability · Published Dec 1, 2025 · Assigned by NLOK
CVE-2025-10101Avast antivirus heap buffer OOB read when scanning a malformed Mach-O file
High 7.8
In plain English
A high-severity out-of-bounds read in Avast Antivirus from Gen Digital. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 9% of all known vulnerabilities).
Official description
Heap buffer out-of-bounds read vulnerability in Avast Antivirus when scanning a malformed Mach-O file may allow Local Execution of Code or Denial-of-Service of the antivirus process. This issue affects Avast Antivirus, AVG Antivirus, Norton Antivirus, Avast One, and Avast Business Antivirus on Windows, macOS, and Linux for virus definition builds before VPS 25090300. The affected scanning logic is delivered through a shared Gen Digital virus definition update stream. The same stream feeds the consumer antivirus products listed in this advisory and other Gen Digital products that embed the same engine. Mitigation flows through this update channel; installations at or above the listed build are not vulnerable regardless of which product consumes the stream.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Gen Digital | Avast Antivirus | 0 – before 25090300 |
| Gen Digital | AVG Antivirus | 0 – before 25090300 |
| Gen Digital | Norton Antivirus | 0 – before 25090300 |
| Gen Digital | Avast One | 0 – before 25090300 |
| Gen Digital | Avast Business Antivirus | 0 – before 25090300 |
Weakness: CWE-125 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H