CVE-2025-7007 Overview
CVE-2025-7007 is a NULL pointer dereference vulnerability [CWE-476] affecting Avast Antivirus on macOS and Avast Antivirus on Linux. The flaw triggers when the antivirus engine scans a malformed Windows Portable Executable (PE) file, causing the scanning process to crash. The issue affects Avast Antivirus version 16.0.0 on macOS and version 3.0.3 on Linux. An attacker who can deliver a crafted PE file to a scanned location can disable the antivirus process, removing on-access protection until the service restarts.
Critical Impact
Successful exploitation crashes the Avast antivirus process on macOS and Linux endpoints, suspending real-time malware scanning and exposing the host to subsequent attacks.
Affected Products
- Avast Antivirus for macOS version 16.0.0
- Avast Antivirus for Linux version 3.0.3
- Endpoints relying on the affected scanner for on-access PE inspection
Discovery Timeline
- 2025-12-01 - CVE-2025-7007 published to NVD
- 2026-04-15 - Last updated in NVD database
Technical Details for CVE-2025-7007
Vulnerability Analysis
The vulnerability resides in the PE file parsing logic used by Avast Antivirus when inspecting Windows executables on non-Windows hosts. When the scanner processes a malformed PE structure, it dereferences a pointer that was never initialized or that resolves to NULL. The result is an unhandled memory access fault that terminates the scanning process. Because antivirus engines parse files automatically through on-access scanning, an attacker only needs to drop a crafted PE file into a scanned directory to trigger the crash. While the flaw does not yield arbitrary code execution, it produces a reliable denial-of-service condition against the security product, weakening host defenses for any follow-on activity.
Root Cause
The root cause is missing validation of pointer values returned during PE header parsing. The scanner trusts fields within the PE structure without confirming that referenced offsets, section tables, or directory entries point to valid memory regions. A malformed file with truncated or manipulated header values forces the parser down a code path where it dereferences a NULL pointer, classified under [CWE-476].
Attack Vector
Exploitation requires local delivery of a malformed PE file to a path the antivirus monitors or to a manually triggered scan target. The attacker needs low-privileged local access and user interaction, such as the user opening a directory, downloading a file, or initiating a scan. The scope is changed because the crash affects a privileged security service distinct from the user delivering the file. No network-level exploitation path has been published.
No verified proof-of-concept code has been released. Refer to the GenDigital Security Advisory for vendor-supplied technical detail.
Detection Methods for CVE-2025-7007
Indicators of Compromise
- Unexpected termination of the Avast scanning daemon on macOS or Linux endpoints
- Crash reports or core dumps referencing the Avast PE parsing modules
- Repeated appearance of small or structurally invalid .exe or .dll files in user-writable directories prior to a scanner crash
Detection Strategies
- Monitor process lifecycle events for the Avast scanning service and alert on abnormal exits or restart loops
- Correlate antivirus service crashes with recent file write events involving Windows PE files on macOS and Linux hosts
- Track signal SIGSEGV events generated by the Avast process and capture the file path that was being scanned
Monitoring Recommendations
- Forward antivirus service logs and system crash logs to a centralized SIEM for correlation across endpoints
- Alert when the antivirus process restarts more than a defined threshold within a short window
- Validate that on-access scanning is active after every service restart, treating gaps as security incidents
How to Mitigate CVE-2025-7007
Immediate Actions Required
- Inventory all macOS and Linux endpoints running Avast Antivirus and identify hosts on versions 16.0.0 (macOS) and 3.0.3 (Linux)
- Apply the vendor-supplied update referenced in the GenDigital security advisory as soon as it is available for your platform
- Restrict the ability of low-privileged local users to drop arbitrary PE files into scanned directories
Patch Information
GenDigital, the parent company of Avast, maintains fix information through its central advisory portal. Review the GenDigital Security Advisory for the fixed build numbers for macOS and Linux, and deploy through your standard endpoint management workflow. Confirm post-patch that the scanner version reported on each host exceeds the vulnerable releases.
Workarounds
- Configure scan exclusions only as a temporary control and remove them once patches are deployed
- Limit interactive logons on Linux and macOS hosts to reduce the population of users who could deliver a malformed PE file
- Enable automatic restart of the Avast scanning service so that a crash does not leave the endpoint unprotected for an extended period
- Monitor for repeated scanner crashes and treat them as potential evidence of exploitation attempts
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
