---
title: errSecUnknownCriticalExtensionFlag
framework: security
role: symbol
role_heading: Global Variable
path: security/errsecunknowncriticalextensionflag
---

# errSecUnknownCriticalExtensionFlag

There is an unknown critical extension flag.

## Declaration

```swift
var errSecUnknownCriticalExtensionFlag: OSStatus { get }
```