diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6ecade6..3d1ca04 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,11 @@
 # Changelog
 
+## [4.0.1](https://github.com/jcamp-code/FluentEmail/compare/v4.0.0...v4.0.1)
+
+### 🩹 Fixes
+
+* Update MailKit to 4.15.1 to fix CRLF injection vulnerability in MimeKit ([CVE-2026-30227](https://github.com/advisories/GHSA-g7hc-96xr-gvvx))
+
 ## [4.0.0](https://github.com/jcamp-code/FluentEmail/compare/v3.8.0...v4.0.0) (2025-10-26)
 
 
diff --git a/src/Senders/FluentEmail.MailKit/FluentEmail.MailKit.csproj b/src/Senders/FluentEmail.MailKit/FluentEmail.MailKit.csproj
index d46b82b..e208c89 100644
--- a/src/Senders/FluentEmail.MailKit/FluentEmail.MailKit.csproj
+++ b/src/Senders/FluentEmail.MailKit/FluentEmail.MailKit.csproj
@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <Description>Send emails via MailKit. The SmtpClient has been deprecated and Microsoft recommends using MailKit instead.</Description>
@@ -19,7 +19,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="MailKit" Version="4.14.1" />
+    <PackageReference Include="MailKit" Version="4.15.1" />
   </ItemGroup>
 
 	<ItemGroup Condition="'$(TargetFramework)' == 'net8.0'">