diff --git a/changelog.d/5821.bugfix b/changelog.d/5821.bugfix
new file mode 100644
index 0000000000..25d8fd2b46
--- /dev/null
+++ b/changelog.d/5821.bugfix
@@ -0,0 +1 @@
+Fixes concurrent modification crash when signing out or launching the app
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/SessionListeners.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/SessionListeners.kt
index 756b9cef83..0dae24e64b 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/SessionListeners.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/SessionListeners.kt
@@ -19,12 +19,13 @@ package org.matrix.android.sdk.internal.session
 import org.matrix.android.sdk.api.extensions.tryOrNull
 import org.matrix.android.sdk.api.session.Session
 import timber.log.Timber
+import java.util.concurrent.CopyOnWriteArraySet
 import javax.inject.Inject
 
 @SessionScope
 internal class SessionListeners @Inject constructor() {
 
-    private val listeners = mutableSetOf<Session.Listener>()
+    private val listeners = CopyOnWriteArraySet<Session.Listener>()
 
     fun addListener(listener: Session.Listener) {
         synchronized(listeners) {