CVE-2026-27749

Avira Internet Security contains a deserialization of untrusted data vulnerability in the System Speedup component. The Avira.SystemSpeedup.RealTimeOptimizer.exe process, which runs with SYSTEM privileges, deserializes data from a file located in C:\\ProgramData using .NET BinaryFormatter without implementing input validation or deserialization safeguards. Because the file can be created or modified by a local user in default configurations, an attacker can supply a crafted serialized payload that is deserialized by the privileged process, resulting in arbitrary code execution as SYSTEM.

• https://support.avira.com/hc/en-us/articles/360010656158-Current-Avira-versions
• https://www.avira.com/en/internet-security
• https://www.gendigital.com/us/en/contact-us/security-advisories/