Index: src/client/cl_campaign.c
===================================================================
--- src/client/cl_campaign.c    (Revision 7917)
+++ src/client/cl_campaign.c    (Arbeitskopie)
@@ -1712,6 +1712,8 @@
        for (i = 0, mis = ccs.mission; i < ccs.numMissions; i++, mis++) {
                /* get mission definition */
                name = MSG_ReadString(sb);
+               mis->def = NULL;
+               mis->cause = NULL;
                for (j = 0; j < numMissions; j++)
                        if (!Q_strncmp(name, missions[j].name, MAX_VAR)) {
                                mis->def = &missions[j];
@@ -1720,6 +1722,16 @@
                if (j >= numMissions)
                        Com_Printf("......warning: Mission '%s' not found\n", name);
 
+               /* ignore incomplete info */
+               if (!mis->def) {
+                       memset(mis, 0, sizeof(actMis_t));
+                       mis--;
+                       i--;
+                       ccs.numMissions--;
+                       Com_Printf("......warning: Incomplete mission info\n");
+                       return qfalse;
+               }
+
                /* get mission type and location */
                mis->def->missionType = MSG_ReadByte(sb);
                mis->def->storyRelated = MSG_ReadByte(sb);
@@ -1736,21 +1748,23 @@
                if (j >= numStageSets)
                        Com_Printf("......warning: Stage set '%s' not found\n", name);
 
+               /* ignore incomplete info */
+               if (!mis->cause) {
+                       memset(mis, 0, sizeof(actMis_t));
+                       mis--;
+                       i--;
+                       ccs.numMissions--;
+                       Com_Printf("......warning: Incomplete mission info\n");
+                       return qfalse;
+               }
+
                /* read position and time */
                mis->realPos[0] = MSG_ReadFloat(sb);
                mis->realPos[1] = MSG_ReadFloat(sb);
                mis->expire.day = MSG_ReadLong(sb);
                mis->expire.sec = MSG_ReadLong(sb);
+
                mis->def->onGeoscape = qtrue;
-
-               /* ignore incomplete info */
-               if (!mis->def || !mis->cause) {
-                       memset(mis, 0, sizeof(actMis_t));
-                       mis--;
-                       i--;
-                       ccs.numMissions--;
-                       Com_Printf("......ignore incomplete mission info\n");
-               }
                /* manually set mission data for a base-attack */
                if (mis->def->missionType == MIS_BASEATTACK) {
                        /* Load IDX of base under attack */
@@ -1766,9 +1780,13 @@
 
        /* stores the select mission on geoscape */
        selectedMission = MSG_ReadLong(sb);
-       if (selectedMission >= 0)
+       if (selectedMission >= 0 && selectedMission < ccs.numMissions) {
                selMis = ccs.mission + selectedMission;
-       else
+               if (!selMis->def) {
+                       Com_Printf("......warning: incomplete mission data\n");
+                       return qfalse;
+               }
+       } else
                selMis = NULL;
 
        /* and now fix the mission pointers or let the aircraft return to base */