diff --git a/ChangeLog b/ChangeLog
index 3ca926813..78664d054 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,12 @@
 mbed TLS ChangeLog (Sorted per branch, date)
 
+= mbed TLS 1.3.15 released 2015-10-xx
+
+Security
+   * Fix potential double free if ssl_set_psk() is called more than once and
+     some allocation fails. Cannot be forced remotely. Found by Guido Vranken,
+     Intelworks.
+
 = mbed TLS 1.3.14 released 2015-10-06
 
 Security
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 7fc9d9908..166b116e7 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -4058,6 +4058,8 @@ int ssl_set_psk( ssl_context *ssl, const unsigned char *psk, size_t psk_len,
     {
         polarssl_free( ssl->psk );
         polarssl_free( ssl->psk_identity );
+        ssl->psk = NULL;
+        ssl->psk_identity = NULL;
     }
 
     if( ( ssl->psk = polarssl_malloc( psk_len ) ) == NULL ||