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    "cveMetadata": {
        "cveId": "CVE-2026-11826",
        "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "state": "PUBLISHED",
        "assignerShortName": "VulnCheck",
        "dateReserved": "2026-06-09T19:53:45.722Z",
        "datePublished": "2026-07-18T13:35:35.639Z",
        "dateUpdated": "2026-07-28T01:48:21.734Z"
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                "dateUpdated": "2026-07-28T01:48:21.734Z"
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            "title": "OpenPLC_v3 Heap-Based Buffer Overflow in Modbus Master getData()",
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                {
                    "lang": "en",
                    "value": "OpenPLC_v3 contains a heap-based buffer overflow in the getData() function in webserver/core/modbus_master.cpp. getData() reads characters between two delimiters into a caller-supplied buffer with no size parameter and no bounds check. In parseConfig() the function is invoked with the 100-byte heap-allocated MB_device.dev_name field. An authenticated attacker with access to the OpenPLC web interface can send a crafted HTTP POST to the /modbus endpoint with an oversized device_name value; the value is persisted to mbconfig.cfg and parsed on load, overflowing dev_name and overwriting adjacent struct fields (protocol at offset 108, dev_address at offset 109, ip_port at offset 210). A 200-byte payload writes 100 bytes past the allocation. The result is heap corruption leading to runtime crash and denial of service of the PLC process control loop, with attacker-controlled overwrite of adjacent configuration fields. The upstream repository was archived on 2026-04-04 and no fix is expected; the vendor has confirmed the issue does not affect OpenPLC Runtime v4."
                }
            ],
            "datePublic": "2026-07-17T00:00:00.000Z",
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                            "cweId": "CWE-122",
                            "description": "Heap-based Buffer Overflow",
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                        "Automatable": "NOT_DEFINED",
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                                "timestamp": "2026-07-20T17:02:00.553936Z",
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