diff --git a/plugins/ice/src/dtls_srtp.vala b/plugins/ice/src/dtls_srtp.vala
index c5b2eb75..81ebfcbc 100644
--- a/plugins/ice/src/dtls_srtp.vala
+++ b/plugins/ice/src/dtls_srtp.vala
@@ -338,7 +338,7 @@ private uint8[] get_fingerprint(X509.Certificate certificate, DigestAlgorithm di
 private string format_fingerprint(uint8[] fingerprint) {
     var sb = new StringBuilder();
     for (int i = 0; i < fingerprint.length; i++) {
-        sb.append("%02x".printf(fingerprint[i]));
+        sb.append("%02X".printf(fingerprint[i]));
         if (i < fingerprint.length - 1) {
             sb.append(":");
         }
diff --git a/xmpp-vala/src/module/xep/0176_jingle_ice_udp/transport_parameters.vala b/xmpp-vala/src/module/xep/0176_jingle_ice_udp/transport_parameters.vala
index 680d7c80..454a82bb 100644
--- a/xmpp-vala/src/module/xep/0176_jingle_ice_udp/transport_parameters.vala
+++ b/xmpp-vala/src/module/xep/0176_jingle_ice_udp/transport_parameters.vala
@@ -151,7 +151,7 @@ public abstract class Xmpp.Xep.JingleIceUdp.IceUdpTransportParameters : Jingle.T
     private string format_fingerprint(uint8[] fingerprint) {
         var sb = new StringBuilder();
         for (int i = 0; i < fingerprint.length; i++) {
-            sb.append("%02x".printf(fingerprint[i]));
+            sb.append("%02X".printf(fingerprint[i]));
             if (i < fingerprint.length - 1) {
                 sb.append(":");
             }