diff --git a/.evergreen/run-mongodb-aws-ecs-test.sh b/.evergreen/run-mongodb-aws-ecs-test.sh
index bcbfff4a08f..2f0fac365ad 100755
--- a/.evergreen/run-mongodb-aws-ecs-test.sh
+++ b/.evergreen/run-mongodb-aws-ecs-test.sh
@@ -13,6 +13,3 @@ source ./.evergreen/prepare-shell.sh # should not run git clone
 
 # load node.js
 source $DRIVERS_TOOLS/.evergreen/init-node-and-npm-env.sh
-
-# run the tests
-npm install aws4
diff --git a/.evergreen/setup-mongodb-aws-auth-tests.sh b/.evergreen/setup-mongodb-aws-auth-tests.sh
index 79ab66e55bc..92b752cbbcc 100644
--- a/.evergreen/setup-mongodb-aws-auth-tests.sh
+++ b/.evergreen/setup-mongodb-aws-auth-tests.sh
@@ -23,8 +23,6 @@ cd $DRIVERS_TOOLS/.evergreen/auth_aws
 
 cd $BEFORE
 
-npm install --no-save aws4
-
 if [ $MONGODB_AWS_SDK = 'false' ]; then rm -rf ./node_modules/@aws-sdk/credential-providers; fi
 
 # revert to show test output
diff --git a/package-lock.json b/package-lock.json
index eb70e77717c..3a7560c5c23 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -20,6 +20,7 @@
         "@microsoft/api-extractor": "^7.49.2",
         "@microsoft/tsdoc-config": "^0.17.1",
         "@mongodb-js/zstd": "^2.0.0",
+        "@types/aws4": "^1.11.6",
         "@types/chai": "^4.3.17",
         "@types/chai-subset": "^1.3.5",
         "@types/express": "^4.17.21",
@@ -33,6 +34,7 @@
         "@types/whatwg-url": "^11.0.5",
         "@typescript-eslint/eslint-plugin": "8.4.0",
         "@typescript-eslint/parser": "8.4.0",
+        "aws4": "^1.13.2",
         "chai": "^4.4.1",
         "chai-subset": "^1.6.0",
         "chalk": "^4.1.2",
@@ -71,6 +73,7 @@
       "peerDependencies": {
         "@aws-sdk/credential-providers": "^3.632.0",
         "@mongodb-js/zstd": "^1.1.0 || ^2.0.0",
+        "aws4": "^1.13.2",
         "gcp-metadata": "^5.2.0",
         "kerberos": "^2.0.1",
         "mongodb-client-encryption": ">=6.0.0 <7",
@@ -84,6 +87,9 @@
         "@mongodb-js/zstd": {
           "optional": true
         },
+        "aws4": {
+          "optional": true
+        },
         "gcp-metadata": {
           "optional": true
         },
@@ -2846,6 +2852,16 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/@types/aws4": {
+      "version": "1.11.6",
+      "resolved": "https://registry.npmjs.org/@types/aws4/-/aws4-1.11.6.tgz",
+      "integrity": "sha512-5CnVUkHNyLGpD9AnOcK66YyP0qvIh6nhJJoeK8zSl5YKikUcUbdB7SlHevUYVqicgeh6j5AJa1qa/h08dSZHoA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@types/node": "*"
+      }
+    },
     "node_modules/@types/body-parser": {
       "version": "1.19.5",
       "resolved": "https://registry.npmjs.org/@types/body-parser/-/body-parser-1.19.5.tgz",
@@ -3542,6 +3558,13 @@
         "node": "*"
       }
     },
+    "node_modules/aws4": {
+      "version": "1.13.2",
+      "resolved": "https://registry.npmjs.org/aws4/-/aws4-1.13.2.tgz",
+      "integrity": "sha512-lHe62zvbTB5eEABUVi/AwVh0ZKY9rMMDhmm+eeyuuUQbQ3+J+fONVQOZyj+DdrvD4BY33uYniyRJ4UJIaSKAfw==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/balanced-match": {
       "version": "1.0.2",
       "resolved": "https://registry.npmjs.org/balanced-match/-/balanced-match-1.0.2.tgz",
diff --git a/package.json b/package.json
index 38e3a891cd5..25530015f0c 100644
--- a/package.json
+++ b/package.json
@@ -32,6 +32,7 @@
   "peerDependencies": {
     "@aws-sdk/credential-providers": "^3.632.0",
     "@mongodb-js/zstd": "^1.1.0 || ^2.0.0",
+    "aws4": "^1.13.2",
     "gcp-metadata": "^5.2.0",
     "kerberos": "^2.0.1",
     "mongodb-client-encryption": ">=6.0.0 <7",
@@ -45,6 +46,9 @@
     "@mongodb-js/zstd": {
       "optional": true
     },
+    "aws4": {
+      "optional": true
+    },
     "kerberos": {
       "optional": true
     },
@@ -68,6 +72,7 @@
     "@microsoft/api-extractor": "^7.49.2",
     "@microsoft/tsdoc-config": "^0.17.1",
     "@mongodb-js/zstd": "^2.0.0",
+    "@types/aws4": "^1.11.6",
     "@types/chai": "^4.3.17",
     "@types/chai-subset": "^1.3.5",
     "@types/express": "^4.17.21",
@@ -81,6 +86,7 @@
     "@types/whatwg-url": "^11.0.5",
     "@typescript-eslint/eslint-plugin": "8.4.0",
     "@typescript-eslint/parser": "8.4.0",
+    "aws4": "^1.13.2",
     "chai": "^4.4.1",
     "chai-subset": "^1.6.0",
     "chalk": "^4.1.2",
diff --git a/src/cmap/auth/mongodb_aws.ts b/src/cmap/auth/mongodb_aws.ts
index d9071496b54..61e2ccc2e63 100644
--- a/src/cmap/auth/mongodb_aws.ts
+++ b/src/cmap/auth/mongodb_aws.ts
@@ -138,8 +138,8 @@ export class MongoDBAWS extends AuthProvider {
     );
 
     const payload: AWSSaslContinuePayload = {
-      a: options.headers.Authorization,
-      d: options.headers['X-Amz-Date']
+      a: `${options.headers?.Authorization ?? ''}`,
+      d: `${options.headers?.['X-Amz-Date'] ?? ''}`
     };
 
     if (sessionToken) {
diff --git a/src/deps.ts b/src/deps.ts
index 0947ca6efc5..27127a3bcc8 100644
--- a/src/deps.ts
+++ b/src/deps.ts
@@ -244,10 +244,10 @@ interface AWS4 {
   };
 }
 
-export const aws4: AWS4 | { kModuleError: MongoMissingDependencyError } = loadAws4();
+export const aws4 = loadAws4();
 
 function loadAws4() {
-  let aws4: AWS4 | { kModuleError: MongoMissingDependencyError };
+  let aws4: typeof import('aws4') | { kModuleError: MongoMissingDependencyError };
   try {
     // eslint-disable-next-line @typescript-eslint/no-require-imports
     aws4 = require('aws4');