CVE-2025-7008: Avast, AVG, Norton Antivirus Heap Buffer Vulnerability – Patch Guide

Technical summary

CVE-2025-7008 is a heap buffer out-of-bounds read (CWE-125) in the antivirus scanning engine shared by multiple Gen Digital products. The vulnerability occurs in the PE file parser when processing malformed .NET metadata structures. Out-of-bounds reads in memory-unsafe operations can leak sensitive data or, when combined with other conditions, facilitate code execution. The attack surface is local—an attacker must be able to place or cause the antivirus to scan a malformed PE file—but no user interaction beyond normal antivirus operation (automatic or manual scan) is required once the trigger file is present. The CVSS score of 7.8 reflects the combination of local attack vector, high confidentiality impact (information disclosure), high integrity impact (code execution potential), and high availability impact (process crash).

Business impact

Organizations running Avast, AVG, Norton, Avast One, or Avast Business antivirus face two material risks: (1) denial of service—the antivirus process crashing, leaving systems temporarily unprotected, and (2) potential local privilege escalation or lateral movement if code execution is achieved. In environments where endpoint protection is a critical control, an antivirus crash could trigger security alerts, require manual remediation, and disrupt business operations. The vulnerability is particularly concerning for business-grade deployments where antivirus is part of a layered defense strategy. Rapid patching via virus definition updates mitigates this risk cleanly without requiring product reinstallation.

Affected systems

Avast Antivirus, AVG Antivirus, Norton Antivirus, Avast One, and Avast Business Antivirus running on Windows, macOS, and Linux are affected if their virus definition build is older than VPS 25021310. Because the vulnerable scanning logic is part of a shared Gen Digital engine, other products consuming the same virus definition stream may also be affected; organizations should cross-reference their specific product lineup against Gen Digital's advisory. Note that the vulnerability requires the antivirus to scan a trigger file, so air-gapped or offline systems may have lower exposure unless file transfers occur.

Exploitability

Exploitability is rated moderate-to-high in practical terms. An attacker needs local file system access to place a malformed PE file where the antivirus will scan it—either through existing local access, via file transfer mechanisms, or by compromising a less-privileged process. The trigger is passive from the antivirus perspective; no user interaction is required beyond the normal scanning process. However, weaponizing an out-of-bounds read into reliable code execution depends on memory layout, ASLR, and heap state, making it a lower-reliability attack than a direct arbitrary code execution flaw. The vulnerability does not appear on the KEV catalog, suggesting no active, widespread in-the-wild exploitation has been formally documented, but organizations should not rely on that as a basis to delay patching.

Remediation

Update virus definitions to build VPS 25021310 or later. This is the definitive fix and applies uniformly across all affected products and platforms. Most users can achieve this through the standard automatic virus definition update mechanism in their antivirus settings; no product upgrade or reinstall is necessary. Verify that your virus definition build has incremented to at least 25021310 post-update. As a temporary mitigation in constrained environments, minimize the scanning of untrusted files and disable automatic scanning of removable media or network shares if operationally feasible, but these measures are poor substitutes for the actual patch.

Patch guidance

Confirm that your antivirus product is set to receive automatic virus definition updates and verify the current definition build in the product's settings or logs. After the automatic update, cross-check that the VPS build is at or above 25021310. For organizations managing multiple endpoints, use your centralized management console (e.g., Avast Business Center or equivalent) to push the update and confirm compliance. If you manage air-gapped systems, manually update virus definitions from an offline source or network share. There is no product version requirement; the vulnerability is patched at the definition level, so all versions of the affected products benefit from the update.

Detection guidance

Monitor antivirus logs and event streams for crash or error events in the scanning engine, which may indicate exploitation attempts. Endpoint detection and response (EDR) tools can flag suspicious local process execution following antivirus crashes. Look for alerts related to unusual file access patterns or malformed PE files being scanned. Collect and quarantine any malformed PE files that trigger antivirus crashes for forensic analysis. Implement file integrity monitoring on directories where untrusted files might arrive (downloads, shared folders, temporary locations). Network-based detection is limited since the vulnerability is triggered locally; focus on endpoint-centric telemetry.

Why prioritize this

Despite the moderate CVSS score, this vulnerability merits prompt attention because: (1) it affects multiple widely-deployed antivirus products, (2) it directly compromises a critical security control, and (3) the fix is simple and low-risk (a definition update with no compatibility concerns). The lack of KEV documentation does not diminish risk; attackers may be developing exploits privately. Prioritize patching within 1–2 weeks in production environments, sooner if you operate high-risk networks.

Risk score, explained

The CVSS 3.1 score of 7.8 (HIGH) reflects: Attack Vector: Local (AV:L)—attacker must place a trigger file on the local system; Attack Complexity: Low (AC:L)—no special conditions needed beyond the malformed file; Privileges Required: None (PR:N)—no special privileges needed to scan a file; User Interaction: Required (UI:R)—but only to trigger the antivirus scan, which is routine; Scope: Unchanged (S:U); Confidentiality: High (C:H)—out-of-bounds read can leak sensitive memory; Integrity: High (I:H)—potential for code execution; Availability: High (A:H)—antivirus process crash. The 7.8 score appropriately weights the severity of the impact against the local-only attack surface.

Frequently asked questions