diff --git a/Dockerfile b/Dockerfile
index 537898fb..35e21323 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM eclipse-temurin:17.0.13_11-jre-focal
+FROM eclipse-temurin:21.0.11_10-jre-noble
 
 ARG jar
 
diff --git a/build.gradle b/build.gradle
index 59daa216..340de6be 100644
--- a/build.gradle
+++ b/build.gradle
@@ -33,10 +33,10 @@ allprojects {
     }
     java {
         toolchain {
-            languageVersion.set(JavaLanguageVersion.of(17))
+            languageVersion.set(JavaLanguageVersion.of(21))
         }
-        sourceCompatibility = JavaVersion.VERSION_17
-        targetCompatibility = JavaVersion.VERSION_17
+        sourceCompatibility = JavaVersion.VERSION_21
+        targetCompatibility = JavaVersion.VERSION_21
     }
 
     tasks.withType(JavaCompile).configureEach {
diff --git a/iexec-sms-library/build.gradle b/iexec-sms-library/build.gradle
index 67dd6969..d47b76b4 100644
--- a/iexec-sms-library/build.gradle
+++ b/iexec-sms-library/build.gradle
@@ -13,8 +13,8 @@ dependencies {
 }
 
 java {
-    sourceCompatibility = JavaVersion.VERSION_17
-    targetCompatibility = JavaVersion.VERSION_17
+    sourceCompatibility = JavaVersion.VERSION_21
+    targetCompatibility = JavaVersion.VERSION_21
     withJavadocJar()
     withSourcesJar()
 }
diff --git a/src/main/java/com/iexec/sms/tee/session/TeeSessionService.java b/src/main/java/com/iexec/sms/tee/session/TeeSessionService.java
index 6fd3a0fc..3dee6424 100644
--- a/src/main/java/com/iexec/sms/tee/session/TeeSessionService.java
+++ b/src/main/java/com/iexec/sms/tee/session/TeeSessionService.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2020-2025 IEXEC BLOCKCHAIN TECH
+ * Copyright 2020-2026 IEXEC BLOCKCHAIN TECH
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -112,7 +112,7 @@ public TeeServicesProperties resolveTeeServiceProperties(final String version) {
     }
 
     private String createSessionId(final String taskId) {
-        final String randomString = RandomStringUtils.randomAlphanumeric(10);
+        final String randomString = RandomStringUtils.secure().nextAlphanumeric(10);
         return String.format("%s0000%s", randomString, taskId);
     }
 
diff --git a/src/test/java/com/iexec/sms/tee/session/scone/SconeSessionMakerServiceTests.java b/src/test/java/com/iexec/sms/tee/session/scone/SconeSessionMakerServiceTests.java
index 8c78e9d2..0a467f14 100644
--- a/src/test/java/com/iexec/sms/tee/session/scone/SconeSessionMakerServiceTests.java
+++ b/src/test/java/com/iexec/sms/tee/session/scone/SconeSessionMakerServiceTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2020-2025 IEXEC BLOCKCHAIN TECH
+ * Copyright 2020-2026 IEXEC BLOCKCHAIN TECH
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -38,6 +38,8 @@
 import org.yaml.snakeyaml.Yaml;
 
 import java.net.MalformedURLException;
+import java.net.URI;
+import java.net.URISyntaxException;
 import java.net.URL;
 import java.util.List;
 import java.util.Map;
@@ -57,9 +59,9 @@ class SconeSessionMakerServiceTests {
 
     static {
         try {
-            MAA_URL_OUT_OF_SERVICE = new URL("https://broken.maa.attestation.service");
-            MAA_URL = new URL("https://maa.attestation.service");
-        } catch (MalformedURLException e) {
+            MAA_URL_OUT_OF_SERVICE = new URI("https://broken.maa.attestation.service").toURL();
+            MAA_URL = new URI("https://maa.attestation.service").toURL();
+        } catch (URISyntaxException | MalformedURLException e) {
             throw new RuntimeException(e);
         }
     }
diff --git a/src/test/java/com/iexec/sms/tee/session/scone/SconeSessionSecurityConfigTests.java b/src/test/java/com/iexec/sms/tee/session/scone/SconeSessionSecurityConfigTests.java
index 6fcec0cd..bb3136e2 100644
--- a/src/test/java/com/iexec/sms/tee/session/scone/SconeSessionSecurityConfigTests.java
+++ b/src/test/java/com/iexec/sms/tee/session/scone/SconeSessionSecurityConfigTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 IEXEC BLOCKCHAIN TECH
+ * Copyright 2025-2026 IEXEC BLOCKCHAIN TECH
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -24,6 +24,8 @@
 import org.junit.jupiter.api.Test;
 
 import java.net.MalformedURLException;
+import java.net.URI;
+import java.net.URISyntaxException;
 import java.net.URL;
 import java.util.List;
 import java.util.Set;
@@ -39,8 +41,8 @@ class SconeSessionSecurityConfigTests {
 
     static {
         try {
-            MAA_URL = new URL("https://maa.attestation.service");
-        } catch (MalformedURLException e) {
+            MAA_URL = new URI("https://maa.attestation.service").toURL();
+        } catch (URISyntaxException | MalformedURLException e) {
             throw new RuntimeException(e);
         }
     }