diff --git a/tests/ci/cdk/README.md b/tests/ci/cdk/README.md
index aeae3cab11f..88ad5552146 100644
--- a/tests/ci/cdk/README.md
+++ b/tests/ci/cdk/README.md
@@ -16,6 +16,11 @@ AWS-LC CI uses AWS CDK to define and deploy AWS resources (e.g. AWS CodeBuild, E
     * step 3: change **Source provider** to **GitHub**. 
     * step 4: click **Connect using OAuth** and **Connect to GitHub**.
     * step 5: follow the OAuth app to grant access.
+* Setup Python environment:
+  * From `aws-lc/tests/ci` run:
+```shell
+python -m pip install -r requirements.txt
+```
 
 ### Minimal permissions:
 
@@ -60,6 +65,12 @@ To setup or update the CI in your account you will need the following IAM permis
 
 ### Commands
 
+These commands are run from `aws-lc/tests/ci/cdk`. \
+If not done previously, bootstrap cdk before running the commands below:
+```shell
+cdk bootstrap aws://${AWS_ACCOUNT_ID}/us-west-2
+```
+
 Note: `GITHUB_REPO_OWNER` specifies the GitHub repo targeted by this CI setup.
 * https://github.com/${GITHUB_REPO_OWNER}/aws-lc.git
 
diff --git a/tests/ci/setup.py b/tests/ci/setup.py
index 8b7cea624db..f3392456277 100644
--- a/tests/ci/setup.py
+++ b/tests/ci/setup.py
@@ -23,7 +23,7 @@
         "aws-cdk-lib==2.74.0",
         "constructs==10.1.314",
         # PyYAML is a YAML parser and emitter for Python. Used to read build_spec.yaml.
-        "pyyaml==5.3.1",
+        "pyyaml==6.0",
         # A formatter for Python code.
         "yapf==0.30.0",
         # Introduced by benchmark framework.
@@ -31,7 +31,7 @@
         # Introduced by Android Device Farm CI.
         "requests",
         "arnparse==0.0.2",
-        "urllib3==1.25.4"
+        "urllib3==1.25.10"
     ],
 
     python_requires=">=3.6",