diff --git a/integration-tests/main-app-test/src/test/java/co/elastic/apm/test/AgentSetupIT.java b/integration-tests/main-app-test/src/test/java/co/elastic/apm/test/AgentSetupIT.java
index fac320dffe..32e6c05903 100644
--- a/integration-tests/main-app-test/src/test/java/co/elastic/apm/test/AgentSetupIT.java
+++ b/integration-tests/main-app-test/src/test/java/co/elastic/apm/test/AgentSetupIT.java
@@ -66,9 +66,11 @@ void testSecurityManagerWarning() {
         try (AgentTestContainer.JarApp app = testAppWithJavaAgent("openjdk:17", AgentFileAccessor.Variant.STANDARD)) {
 
             app.withSecurityManager(null)
-                .waitingFor(Wait.forLogMessage(expectedMsg, 1))
+                // using a dummy command since testcontainers 1.21.0 as waiting on stderr msg is not working anymore
+                // when the container fails to start. Likely related to https://github.com/testcontainers/testcontainers-java/issues/9956
+                .waitingFor(Wait.forLogMessage(".*processing of -javaagent failed, processJavaStart failed.*", 1))
                 // we expect startup to fail fast as JVM should not even properly start
-                .withStartupTimeout(Duration.ofSeconds(1));
+                .withStartupTimeout(Duration.ofSeconds(3));
 
             app.start();
 
@@ -83,7 +85,7 @@ void testSecurityManagerWithPolicy(@TempDir Path temp) throws IOException {
 
         // use a 'grant all' policy for now
         Files.write(tempPolicy, Arrays.asList(
-            "grant codeBase \"file:///tmp/elastic-apm-agent.jar\" {",
+            "grant codeBase \"file:///agent.jar\" {",
             "  permission java.security.AllPermission;",
             "};"), StandardOpenOption.CREATE
         );
diff --git a/pom.xml b/pom.xml
index 394dfe67a7..569b22c4c2 100644
--- a/pom.xml
+++ b/pom.xml
@@ -139,7 +139,7 @@
         <!-- used both for plugin & annotations dependency -->
         <version.animal-sniffer>1.17</version.animal-sniffer>
 
-        <version.testcontainers>1.20.3</version.testcontainers>
+        <version.testcontainers>1.21.0</version.testcontainers>
 
         <!-- latest version compiled for java 11 -->
         <version.jsonunit>2.38.0</version.jsonunit>