In IGEL OS before 11, Secure Boot can be bypassed because the igel-flash-driver module improperly verifies a cryptographic signature.

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

• microsoft windows server 2012all versions
• microsoft windows server 2012r2
• microsoft windows server 2016before 10.0.14393.8519
• microsoft windows server 2019before 10.0.17763.7919
• microsoft windows server 2022before 10.0.20348.4294
• microsoft windows server 2022 23h2before 10.0.25398.1913
• microsoft windows server 2025before 10.0.26100.6899

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Root cause

The verifier takes the algorithm to verify with from the token’s own header. Untrusted data ends up deciding its own verification rule.

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

1const claims = jwt.verify(token, publicKey);

1const claims = jwt.verify(token, publicKey, {2  algorithms: ["RS256"],3  issuer: "https://id.example.com",4  audience: "portal",5});

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.