diff --git a/backend/requirements-dev.txt b/backend/requirements-dev.txt
index ff61c4f..9230120 100644
--- a/backend/requirements-dev.txt
+++ b/backend/requirements-dev.txt
@@ -1,7 +1,7 @@
 # Development and testing dependencies
 pytest==7.4.3
 pytest-asyncio==0.21.1
-black==25.11.0
+black==26.1.0
 isort==5.12.0
 flake8==6.1.0
 
diff --git a/backend/requirements.txt b/backend/requirements.txt
index eb119d4..be19d02 100644
--- a/backend/requirements.txt
+++ b/backend/requirements.txt
@@ -15,7 +15,7 @@ aiosqlite==0.19.0
 # Authentication and Security
 python-jose[cryptography]==3.3.0
 passlib[bcrypt]==1.7.4
-python-multipart==0.0.20
+python-multipart==0.0.22
 bcrypt==4.1.2
 cryptography==46.0.4
 
@@ -39,7 +39,7 @@ emails==0.6
 jinja2==3.1.6
 
 # Validation and Serialization
-marshmallow==4.0.1
+marshmallow==4.1.2
 cerberus==1.3.5
 
 # Utilities
@@ -53,7 +53,7 @@ forex-python==1.8
 
 # PDF and Document Generation
 reportlab==4.0.7
-weasyprint==60.2
+weasyprint==68.0
 
 # Production and Monitoring
 gunicorn==23.0.0
diff --git a/requirements-linux.txt b/requirements-linux.txt
index 46ef968..97d7d69 100644
--- a/requirements-linux.txt
+++ b/requirements-linux.txt
@@ -37,7 +37,7 @@ emails==0.6
 jinja2==3.1.6
 
 # Validation and Serialization
-marshmallow==4.2.2
+marshmallow==4.1.2
 cerberus==1.3.5
 
 # Utilities
diff --git a/requirements-windows.txt b/requirements-windows.txt
index 40d8de0..483be65 100644
--- a/requirements-windows.txt
+++ b/requirements-windows.txt
@@ -36,7 +36,7 @@ emails==0.6
 jinja2==3.1.6
 
 # Validation and Serialization
-marshmallow==4.2.2
+marshmallow==4.1.2
 cerberus==1.3.5
 
 # Utilities
diff --git a/requirements.txt b/requirements.txt
index b85abd0..7122452 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -38,7 +38,7 @@ emails==0.6
 jinja2==3.1.6
 
 # Validation and Serialization
-marshmallow==4.2.2
+marshmallow==4.1.2
 cerberus==1.3.5
 
 # Utilities