diff --git a/java/android/OlmLibSdk/olm-sdk/src/main/jni/olm_inbound_group_session.cpp b/java/android/OlmLibSdk/olm-sdk/src/main/jni/olm_inbound_group_session.cpp
index 09995ab..297f0f5 100644
--- a/java/android/OlmLibSdk/olm-sdk/src/main/jni/olm_inbound_group_session.cpp
+++ b/java/android/OlmLibSdk/olm-sdk/src/main/jni/olm_inbound_group_session.cpp
@@ -150,7 +150,7 @@ JNIEXPORT jstring OLM_INBOUND_GROUP_SESSION_FUNC_DEF(sessionIdentifierJni)(JNIEn
         size_t lengthSessionId = olm_inbound_group_session_id_length(sessionPtr);
         LOGD(" ## sessionIdentifierJni(): inbound group session lengthSessionId=%lu",lengthSessionId);
 
-        if(NULL == (sessionIdPtr = (uint8_t*)malloc(lengthSessionId*sizeof(uint8_t))))
+        if(NULL == (sessionIdPtr = (uint8_t*)malloc((lengthSessionId+1)*sizeof(uint8_t))))
         {
            LOGE(" ## sessionIdentifierJni(): failure - inbound group session identifier allocation OOM");
         }
@@ -228,7 +228,7 @@ JNIEXPORT jstring OLM_INBOUND_GROUP_SESSION_FUNC_DEF(decryptMessageJni)(JNIEnv *
                 LOGD(" ## decryptMessageJni(): maxPlaintextLength=%lu",maxPlainTextLength);
 
                 // allocate output decrypted message
-                plainTextMsgPtr = static_cast<uint8_t*>(malloc(maxPlainTextLength*sizeof(uint8_t)));
+                plainTextMsgPtr = static_cast<uint8_t*>(malloc((maxPlainTextLength+1)*sizeof(uint8_t)));
 
                 // decrypt, but before reload encrypted buffer (previous one was destroyed)
                 memcpy(tempEncryptedPtr, encryptedMsgPtr, encryptedMsgLength);
diff --git a/java/android/OlmLibSdk/olm-sdk/src/main/jni/olm_outbound_group_session.cpp b/java/android/OlmLibSdk/olm-sdk/src/main/jni/olm_outbound_group_session.cpp
index 42d8901..4cbd10b 100644
--- a/java/android/OlmLibSdk/olm-sdk/src/main/jni/olm_outbound_group_session.cpp
+++ b/java/android/OlmLibSdk/olm-sdk/src/main/jni/olm_outbound_group_session.cpp
@@ -150,7 +150,7 @@ JNIEXPORT jstring OLM_OUTBOUND_GROUP_SESSION_FUNC_DEF(sessionIdentifierJni)(JNIE
         size_t lengthSessionId = olm_outbound_group_session_id_length(sessionPtr);
         LOGD(" ## sessionIdentifierJni(): outbound group session lengthSessionId=%lu",lengthSessionId);
 
-        if(NULL == (sessionIdPtr = (uint8_t*)malloc(lengthSessionId*sizeof(uint8_t))))
+        if(NULL == (sessionIdPtr = (uint8_t*)malloc((lengthSessionId+1)*sizeof(uint8_t))))
         {
            LOGE(" ## sessionIdentifierJni(): failure - outbound identifier allocation OOM");
         }
@@ -227,7 +227,7 @@ JNIEXPORT jstring OLM_OUTBOUND_GROUP_SESSION_FUNC_DEF(sessionKeyJni)(JNIEnv *env
         size_t sessionKeyLength = olm_outbound_group_session_key_length(sessionPtr);
         LOGD(" ## sessionKeyJni(): sessionKeyLength=%lu",sessionKeyLength);
 
-        if(NULL == (sessionKeyPtr = (uint8_t*)malloc(sessionKeyLength*sizeof(uint8_t))))
+        if(NULL == (sessionKeyPtr = (uint8_t*)malloc((sessionKeyLength+1)*sizeof(uint8_t))))
         {
            LOGE(" ## sessionKeyJni(): failure - session key allocation OOM");
         }
@@ -285,7 +285,7 @@ JNIEXPORT jstring OLM_OUTBOUND_GROUP_SESSION_FUNC_DEF(encryptMessageJni)(JNIEnv
 
         // compute max encrypted length
         size_t encryptedMsgLength = olm_group_encrypt_message_length(sessionPtr,clearMsgLength);
-        if(NULL == (encryptedMsgPtr = (uint8_t*)malloc(encryptedMsgLength*sizeof(uint8_t))))
+        if(NULL == (encryptedMsgPtr = (uint8_t*)malloc((encryptedMsgLength+1)*sizeof(uint8_t))))
         {
             LOGE(" ## encryptMessageJni(): failure - encryptedMsgPtr buffer OOM");
         }
diff --git a/java/android/OlmLibSdk/olm-sdk/src/main/jni/olm_session.cpp b/java/android/OlmLibSdk/olm-sdk/src/main/jni/olm_session.cpp
index 889e993..c02d390 100644
--- a/java/android/OlmLibSdk/olm-sdk/src/main/jni/olm_session.cpp
+++ b/java/android/OlmLibSdk/olm-sdk/src/main/jni/olm_session.cpp
@@ -497,7 +497,7 @@ JNIEXPORT jint OLM_SESSION_FUNC_DEF(encryptMessageJni)(JNIEnv *env, jobject thiz
             // alloc buffer for encrypted message
             size_t clearMsgLength = (size_t)env->GetStringUTFLength(aClearMsg);
             size_t encryptedMsgLength = olm_encrypt_message_length(sessionPtr, clearMsgLength);
-            if(NULL == (encryptedMsgPtr = (void*)malloc(encryptedMsgLength*sizeof(uint8_t))))
+            if(NULL == (encryptedMsgPtr = (void*)malloc((encryptedMsgLength+1)*sizeof(uint8_t))))
             {
                 LOGE("## encryptMessageJni(): failure - encryptedMsgPtr buffer OOM");
             }
@@ -640,7 +640,7 @@ JNIEXPORT jstring OLM_SESSION_FUNC_DEF(decryptMessageJni)(JNIEnv *env, jobject t
             LOGD("##  decryptMessageJni(): maxPlaintextLength=%lu",maxPlainTextLength);
 
             // allocate output decrypted message
-            plainTextMsgPtr = static_cast<void*>(malloc(maxPlainTextLength*sizeof(uint8_t)));
+            plainTextMsgPtr = static_cast<void*>(malloc((maxPlainTextLength+1)*sizeof(uint8_t)));
 
             // decrypt, but before reload encrypted buffer (previous one was destroyed)
             memcpy(tempEncryptedPtr, encryptedMsgPtr, encryptedMsgLength);
@@ -705,7 +705,7 @@ JNIEXPORT jstring OLM_SESSION_FUNC_DEF(getSessionIdentifierJni)(JNIEnv *env, job
     {
         LOGE("## getSessionIdentifierJni(): failure - invalid Session ptr=NULL");
     }
-    else if(NULL == (sessionIdPtr = (void*)malloc(lengthSessionId*sizeof(uint8_t))))
+    else if(NULL == (sessionIdPtr = (void*)malloc((lengthSessionId+1)*sizeof(uint8_t))))
     {
        LOGE("## getSessionIdentifierJni(): failure - identifier allocation OOM");
     }