---
title: Swift-SDK - 5.4.2
slug: feature-experimentation/release-notes/swift-sdk-5-4-2
docTags: 
createdAt: 2026-07-20T15:45:00.344Z
---

## 5.4.2

July 9, 2026

### Fixes

- Use attribute id instead of key for CMAB prediction requests ([#648](https://github.com/optimizely/swift-sdk/pull/648))
- fix: defer NWPathMonitor creation to avoid crash during multi-SDK startup ([#650](https://github.com/optimizely/swift-sdk/pull/650))
- fix: prevent EXC\_BAD\_ACCESS from premature URLSession deallocation ([#649](https://github.com/optimizely/swift-sdk/pull/649))
- Replace non-numeric holdout placeholder IDs in event-construction tests ([#646](https://github.com/optimizely/swift-sdk/pull/646))

[https://github.com/optimizely/swift-sdk/releases/tag/v5.4.2](https://github.com/optimizely/swift-sdk/releases/tag/v5.4.2)