diff --git a/CHANGELOG.md b/CHANGELOG.md
index f99328b247..59a23d5307 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,6 +18,7 @@ ENHANCEMENTS:
 * Harden security of the app gateway. ([#4863](https://github.com/microsoft/AzureTRE/pull/4863))
 * Pass OIDC vars directly to the devcontainer ([#4871](https://github.com/microsoft/AzureTRE/issues/4871))
 * Update `picomatch` package to v2.3.2 and v4.0.4 to address security vulnerabilities ([#4887](https://github.com/microsoft/AzureTRE/issues/4887))
+* Update `aiohttp`, `pytest` dependencies to patched versions to address Dependabot security alerts.
 
 BUG FIXES:
 * Fix OpenAPI/schema sample generation for `get_sample_operation` step parameters. ([#4864](https://github.com/microsoft/AzureTRE/issues/4864))
diff --git a/airlock_processor/requirements-dev.txt b/airlock_processor/requirements-dev.txt
index 1714408a37..5f82229dfc 100644
--- a/airlock_processor/requirements-dev.txt
+++ b/airlock_processor/requirements-dev.txt
@@ -1,3 +1,3 @@
 # Dev requirements
-pytest==8.3.3
+pytest==9.0.3
 mock==5.2.0
diff --git a/api_app/requirements-dev.txt b/api_app/requirements-dev.txt
index ae35b66de1..2a60d6e132 100644
--- a/api_app/requirements-dev.txt
+++ b/api_app/requirements-dev.txt
@@ -2,4 +2,4 @@
 pytest-asyncio==0.24.0
 httpx==0.28.1
 mock==5.2.0
-pytest==8.3.3
+pytest==9.0.3
diff --git a/api_app/requirements.txt b/api_app/requirements.txt
index 195b468a28..1195c2ab8e 100644
--- a/api_app/requirements.txt
+++ b/api_app/requirements.txt
@@ -1,4 +1,4 @@
-aiohttp==3.13.3
+aiohttp==3.13.4
 azure-core==1.38.0
 azure-cosmos==4.14.3
 azure-eventgrid==4.22.0
diff --git a/cli/requirements.txt b/cli/requirements.txt
index 6ff31f310b..82b05cbab2 100644
--- a/cli/requirements.txt
+++ b/cli/requirements.txt
@@ -8,4 +8,4 @@ pygments==2.19.2
 PyJWT==2.10.1
 azure-cli-core==2.68.0
 azure-identity==1.25.1
-aiohttp==3.13.3
+aiohttp==3.13.4
diff --git a/cli/setup.py b/cli/setup.py
index 5a88a85f79..5f0ee50a03 100644
--- a/cli/setup.py
+++ b/cli/setup.py
@@ -49,7 +49,7 @@
         "PyJWT==2.10.1",
         "azure-cli-core==2.68.0",
         "azure-identity==1.25.1",
-        "aiohttp==3.13.3"
+        "aiohttp==3.13.4"
     ],
 
     namespace_packages=[],
diff --git a/e2e_tests/requirements.txt b/e2e_tests/requirements.txt
index d318c0cc9d..165f5ec459 100644
--- a/e2e_tests/requirements.txt
+++ b/e2e_tests/requirements.txt
@@ -1,6 +1,6 @@
 # API
 httpx==0.28.1
-pytest==8.3.3
+pytest==9.0.3
 pytest-asyncio==0.24.0
 starlette==0.50.0
 pytest-timeout==2.2.0
diff --git a/resource_processor/vmss_porter/requirements.txt b/resource_processor/vmss_porter/requirements.txt
index b984362eb0..0e3a351a49 100644
--- a/resource_processor/vmss_porter/requirements.txt
+++ b/resource_processor/vmss_porter/requirements.txt
@@ -1,4 +1,4 @@
-aiohttp==3.13.3
+aiohttp==3.13.4
 azure-cli-core==2.68.0
 azure-identity==1.25.1
 azure-monitor-opentelemetry==1.6.4