Problem
Brake fluid is leaking from the rear of the brake master cylinder bore
![500x370-hydraulics1-DeNoiseAI-standard](https://www.advicsaftermarket.com/wp-content/uploads/2022/09/500x370-hydraulics1-DeNoiseAI-standard.png)
Likely Cause
- Brake master cylinder seals are damaged and leaking
- Vacuum booster input seal and/or pushrod misalignment
Solutions
- Check if vacuum booster input seal and pushrod are properly aligned
- Replace slide pin boots and sleeves
- Replace a brake master cylinder if necessary