CVE-2025-8351 | Scanning a malformed file in Avast Antivirus 8.3.70.94 on MacOS may result in remote code execution

Heap-based Buffer Overflow, Out-of-bounds Read vulnerability in Avast Antivirus on MacOS when scanning a malformed file may allow Local Execution of Code or Denial-of-Service of the anitvirus engine process.This issue affects Antivirus: from 8.3.70.94 before 8.3.70.98.

Published: 2025-12-01 Last update: 2026-04-15 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2025-8351 is rated Moderate Risk (42.6/100): CVSS Critical severity, with low exploitation likelihood (EPSS 0.06%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-8351

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-12-02 0.06%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-8351

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.0 3.1 CRITICAL
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.2 6.0 [email protected]

Weakness enumeration for CVE-2025-8351

Affected software / configurations for CVE-2025-8351

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2025-8351

cvelogic Threat Intelligence