Zimbra Releases/10.1.15

Zimbra Daffodil (v10.1.15) Patch Release

Release Date: Nov 25, 2025

Fixed Issues

• The ZCS 10.1.13 release introduced an upgraded AntiSamy engine designed to strictly filter malicious code and elevate platform security standards. Post-release analysis and customer feedback indicates that this stricter security posture enforces CSS compliance rigorously, which may occasionally affect the rendering of incoming emails that use non-standard, legacy, or invalid CSS formatting (common in third-party marketing and bulk mailers).
  
  This update includes a Rendering Optimization enhancement that refines the parser logic to better distinguish between potential security threats and harmless non-standard CSS attributes. This maintains all security safeguards while ensuring diverse HTML email formats render as intended without unnecessary sanitization interference.
  
  We recommend applying this update to ensure consistent rendering for all incoming mail streams.

Packages

The package lineup for this release is:

zimbra-patch                                      ->  10.1.15.1763965064-2
zimbra-common-core-libs                           ->  10.1.15.1762779814-1
zimbra-mbox-store-libs                            ->  10.1.15.1762779814-1

Patch Installation

Please refer to below link to install 10.1.15 (Nov 25 2025):

Patch Installation

Quick note: Open Source repo

The steps to download, build, and see our code via Github can be found here: https://github.com/Zimbra/zm-build