Avira Antivirus CVE-2025-7018

Exploitation requires that a malformed Windows PE file be introduced to a system running an unpatched Avira Antivirus engine build (prior to 8.3.70.64) and that the engine scan the file - either through on-access scanning triggered by file creation or access, or through a user- or schedule-initiated manual scan. The CVSS vector AV:L/UI:R confirms local file presence and a scan trigger event are both required; there is no network-exposed attack surface in the engine's parsing path itself. Exploitation is limited to a denial-of-service impact only - no code execution or data exposure results. The trigger is a Windows PE file format regardless of the host OS, meaning macOS and Linux deployments of Avira are equally affected if their engines process PE files (e.g., scanning files downloaded from Windows environments or shared network drives). No authentication is required to place a file in a scanned location, but physical or logical access to the endpoint is necessary.

The CVSS 3.1 score of 5.5 (Medium) is consistent with the real-world impact profile: AV:L limits exploitation to scenarios where the malformed file reaches the local scanning context, and UI:R further constrains it to situations where a scan is triggered. The impact is exclusively availability (A:H, C:N, I:N), meaning successful exploitation crashes the antivirus engine but does not expose data or allow code execution. There is no KEV listing and no public POC identified, which aligns with a moderate-priority vulnerability. EPSS data was not provided in the intelligence feed, so exploitation probability cannot be quantified. The primary real-world risk is an attacker deliberately disabling endpoint protection as a precursor to a broader attack - a technique sometimes used to neuter defenses before deploying malware. This secondary risk elevates practical concern beyond the raw CVSS score, but only in targeted attack scenarios. No conflicting signals in the available data.

An attacker crafts a malformed Windows PE binary - for example, a file with a corrupted PE header or an invalid section table - and delivers it to a target system via email attachment, file share, or a malicious download link. When Avira's on-access scanner or a user-initiated scan processes the file, the engine's PE parser dereferences a null pointer, immediately crashing the antivirus engine process. No public POC exists at time of analysis, but crafting malformed PE files is a well-understood technique requiring no advanced capability.