/* strip > and < from string */ void strip_html_brackets(char *buffer){ register int x; register int y; register int z; if(buffer==NULL || buffer[0]=='\x0') return; /* remove all occurances in string */ z=(int)strlen(buffer); for(x=0,y=0;x<z;x++){ if(buffer[x]=='<' || buffer[x]=='>') continue; buffer[y++]=buffer[x]; } buffer[y++]='\x0'; return; } ----------- statusmap.c ----------- /* we found the layer argument */ else if(!strcmp(variables[x],"layer")){ x++; if(variables[x]==NULL){ error=TRUE; break; } strip_html_brackets(variables[x]); add_layer(variables[x]); } ----------- Problem in "statusmap.c" ----------- /* print layer url info */ void print_layer_url(int get_method){ layer *temp_layer; for(temp_layer=layer_list;temp_layer!=NULL;temp_layer=temp_layer->next){ if(get_method==TRUE) printf("&layer=%s",temp_layer->layer_name); <-- no "escape_string" else printf("<input type='hidden' name='layer' value='%s'>\n",escape_string(temp_layer->layer_name)); } ========= Solution: ========= if(get_method==TRUE) /* printf("&layer=%s",temp_layer->layer_name); */ printf("&layer=%s",escape_string(temp_layer->layer_name)); ==================== Disclosure Timeline: ==================== 09-Mar-2011 - informed developers 09-Mar-2011 - post on Nagios Tracker - http://tracker.nagios.org/view.php?id=207 09-Mar-2011 - Release date of this security advisory 10-Mar-2011 - post on BugTraq - http://www.securityfocus.com/archive/1/516934/30/0/threaded ======== Credits: ======== Vulnerability found and advisory written by Stefan Schurtz. =========== References: =========== http://www.nagios.org http://www.rul3z.de/advisories/SSCHADV2011-002.txt