What’s Vulnerable › Vulnerabilities

CVE-2026-27749: Avira Internet Security System Speedup Insecure Deserialization

• Severity: high (CVSS 7.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-03-05 · updated 2026-06-17
• Weakness: CWE-502

Description

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.

Affected products

• Gen Digital Inc. Avira Internet Security: before 1.1.114.3113 — fixed in 1.1.114.3113

How to fix

Upgrade to a fixed version: Gen Digital Inc. Avira Internet Security 1.1.114.3113. Check the vendor advisory for mitigations.

References

• 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/

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