diff --git a/org.hl7.fhir.dstu3/pom.xml b/org.hl7.fhir.dstu3/pom.xml
index de2223d63c..d998ac341e 100644
--- a/org.hl7.fhir.dstu3/pom.xml
+++ b/org.hl7.fhir.dstu3/pom.xml
@@ -61,6 +61,16 @@
             <artifactId>okhttp</artifactId>
             <optional>true</optional>
         </dependency>
+        <dependency>
+            <groupId>com.squareup.okio</groupId>
+            <artifactId>okio</artifactId>
+            <optional>true</optional>
+        </dependency>
+        <dependency>
+            <groupId>com.squareup.okio</groupId>
+            <artifactId>okio-jvm</artifactId>
+            <optional>true</optional>
+        </dependency>
 
         <!-- Apache POI -->
         <dependency>
diff --git a/org.hl7.fhir.r4/pom.xml b/org.hl7.fhir.r4/pom.xml
index 00d596acbe..3a30dd2598 100644
--- a/org.hl7.fhir.r4/pom.xml
+++ b/org.hl7.fhir.r4/pom.xml
@@ -68,11 +68,23 @@
 			<artifactId>httpclient</artifactId>
 			<optional>true</optional>
 		</dependency>
+
 		<dependency>
 			<groupId>com.squareup.okhttp3</groupId>
 			<artifactId>okhttp</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>com.squareup.okio</groupId>
+			<artifactId>okio</artifactId>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>com.squareup.okio</groupId>
+			<artifactId>okio-jvm</artifactId>
+			<optional>true</optional>
+		</dependency>
+
 		<dependency>
 			<groupId>org.hl7.fhir.testcases</groupId>
 			<artifactId>fhir-test-cases</artifactId>
diff --git a/org.hl7.fhir.r4b/pom.xml b/org.hl7.fhir.r4b/pom.xml
index 2cc0ac0cf8..83af6a56c8 100644
--- a/org.hl7.fhir.r4b/pom.xml
+++ b/org.hl7.fhir.r4b/pom.xml
@@ -78,7 +78,17 @@
 			<optional>true</optional>
 			<scope>test</scope>
 		</dependency>
-		
+		<dependency>
+			<groupId>com.squareup.okio</groupId>
+			<artifactId>okio</artifactId>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>com.squareup.okio</groupId>
+			<artifactId>okio-jvm</artifactId>
+			<optional>true</optional>
+		</dependency>
+
 		<!-- Apache POI -->
 		<dependency>
 			<groupId>org.apache.poi</groupId>
diff --git a/org.hl7.fhir.r5/pom.xml b/org.hl7.fhir.r5/pom.xml
index dd253fa57c..08d2069929 100644
--- a/org.hl7.fhir.r5/pom.xml
+++ b/org.hl7.fhir.r5/pom.xml
@@ -106,6 +106,16 @@
 			<artifactId>logging-interceptor</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>com.squareup.okio</groupId>
+			<artifactId>okio</artifactId>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>com.squareup.okio</groupId>
+			<artifactId>okio-jvm</artifactId>
+			<optional>true</optional>
+		</dependency>
 
 		<dependency>
 			<groupId>org.projectlombok</groupId>
diff --git a/org.hl7.fhir.utilities/pom.xml b/org.hl7.fhir.utilities/pom.xml
index 475ec5a2a2..180f2499de 100644
--- a/org.hl7.fhir.utilities/pom.xml
+++ b/org.hl7.fhir.utilities/pom.xml
@@ -52,6 +52,18 @@
             <optional>true</optional>
         </dependency>
 
+        <dependency>
+            <groupId>com.squareup.okio</groupId>
+            <artifactId>okio</artifactId>
+            <optional>true</optional>
+        </dependency>
+
+        <dependency>
+            <groupId>com.squareup.okio</groupId>
+            <artifactId>okio-jvm</artifactId>
+            <optional>true</optional>
+        </dependency>
+
         <dependency>
             <groupId>org.projectlombok</groupId>
             <artifactId>lombok</artifactId>
diff --git a/org.hl7.fhir.validation.cli/pom.xml b/org.hl7.fhir.validation.cli/pom.xml
index a5e2a4a858..c63ba2d96c 100644
--- a/org.hl7.fhir.validation.cli/pom.xml
+++ b/org.hl7.fhir.validation.cli/pom.xml
@@ -242,6 +242,20 @@
             <scope>compile</scope>
         </dependency>
 
+        <dependency>
+            <groupId>com.squareup.okio</groupId>
+            <artifactId>okio</artifactId>
+            <optional>false</optional>
+            <scope>compile</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>com.squareup.okio</groupId>
+            <artifactId>okio-jvm</artifactId>
+            <optional>false</optional>
+            <scope>compile</scope>
+        </dependency>
+
         <dependency>
             <groupId>org.antlr</groupId>
             <artifactId>ST4</artifactId>
diff --git a/org.hl7.fhir.validation/pom.xml b/org.hl7.fhir.validation/pom.xml
index 055db9aa3c..4a7d6c8255 100644
--- a/org.hl7.fhir.validation/pom.xml
+++ b/org.hl7.fhir.validation/pom.xml
@@ -173,6 +173,18 @@
             <optional>true</optional>
         </dependency>
 
+        <dependency>
+            <groupId>com.squareup.okio</groupId>
+            <artifactId>okio</artifactId>
+            <optional>true</optional>
+        </dependency>
+
+        <dependency>
+            <groupId>com.squareup.okio</groupId>
+            <artifactId>okio-jvm</artifactId>
+            <optional>true</optional>
+        </dependency>
+
         <!-- Lombok Until I get Around to Rewriting Everything in Kotlin -->
         <dependency>
             <groupId>org.projectlombok</groupId>
diff --git a/pom.xml b/pom.xml
index 9d61f7e09e..649202ea91 100644
--- a/pom.xml
+++ b/pom.xml
@@ -26,7 +26,7 @@
         <junit_platform_launcher_version>1.8.2</junit_platform_launcher_version>
         <maven_surefire_version>3.0.0-M5</maven_surefire_version>
         <maven_clean_version>3.1.0</maven_clean_version>
-        <okhttp.version>4.10.0</okhttp.version>
+        <okhttp.version>4.11.0</okhttp.version>
         <jacoco_version>0.8.9</jacoco_version>
         <lombok_version>1.18.22</lombok_version>
         <byte_buddy_version>1.12.14</byte_buddy_version>
@@ -206,15 +206,38 @@
                         <groupId>org.jetbrains</groupId>
                         <artifactId>annotations</artifactId>
                     </exclusion>
+                    <exclusion>
+                        <groupId>com.squareup.okio</groupId>
+                        <artifactId>okio</artifactId>
+                    </exclusion>
+                    <!-- Excluding brotli impl until https://github.com/square/okhttp/issues/7738 is resolved -->
+                    <exclusion>
+                        <groupId>com.squareup.okhttp3</groupId>
+                        <artifactId>okhttp-brotli</artifactId>
+                    </exclusion>
+                    <exclusion>
+                        <groupId>com.squareup.okio</groupId>
+                        <artifactId>okio-jvm</artifactId>
+                    </exclusion>
                 </exclusions>
             </dependency>
 
-            <!-- Included because okttp3 used a vulnerable version -->
+            <!-- Included because okttp3 used vulnerable versions -->
             <dependency>
                 <groupId>org.jetbrains</groupId>
                 <artifactId>annotations</artifactId>
                 <version>16.0.1</version>
             </dependency>
+            <dependency>
+                <groupId>com.squareup.okio</groupId>
+                <artifactId>okio</artifactId>
+                <version>3.4.0</version>
+            </dependency>
+            <dependency>
+                <groupId>com.squareup.okio</groupId>
+                <artifactId>okio-jvm</artifactId>
+                <version>3.4.0</version>
+            </dependency>
 
             <dependency>
                 <groupId>com.squareup.okhttp3</groupId>