https://vulnerability.circl.lu/sightings/feed 2026-07-16T09:52:26.672352+00:00 Vulnerability-Lookup info@circl.lu python-feedgen Contains only the most 10 recent sightings. https://vulnerability.circl.lu/sighting/5cde41b0-1ffe-4598-99bf-4b8b6d9d34ee/export 2026-07-16T09:52:26.687030+00:00 Automation user https://cvepremium.circl.lu/user/automation {"uuid": "5cde41b0-1ffe-4598-99bf-4b8b6d9d34ee", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "9f56dd64-161d-43a6-b9c3-555944290a09", "vulnerability": "CVE-2026-51539", "type": "seen", "source": "https://gist.github.com/MrAlaskan/f22dcf01a5dd90da1b191fcee9043a32", "content": "# Security Advisory: CVE-2026-51539\n\n## Vulnerability Information\n* **CVE ID:** CVE-2026-51539\n* **Vendor:** libmodbus\n* **Product:** libmodbus (Version 3.1.12)\n* **Vulnerability Type:** CWE-400: Uncontrolled Resource Consumption\n* **Attack Type:** Remote, Unauthenticated\n* **Impact:** Denial of Service (DoS)\n\n## Description\nA Denial of Service vulnerability exists in the receive loop of libmodbus 3.1.12 on Windows. A remote attacker can abuse timeout handling during network read operations to keep the server blocked in the receive path, preventing legitimate Modbus communication.\n\n## Affected Component\nThe vulnerability affects the message receive logic in `src/modbus.c`, specifically the `_modbus_receive_msg` function and its handling of timeouts using `select()` on Windows environments.\n\n## Attack Vectors\nAn unauthenticated, remote attacker with network access to the target Modbus TCP service can exploit this vulnerability by connecting to the configured Modbus TCP port.\n\nThe attacker can then send a Modbus request slowly, transmitting data in small fragments with pauses shorter than the configured receive timeout. Due to improper timeout accounting on Windows, the receive timeout may be effectively restarted for each received fragment, causing the server to remain in the receive loop for an extended period.\n\nSuccessful exploitation can block the affected server from processing legitimate client requests, resulting in a Denial of Service condition.\n\n## References\n* GitHub Issue: https://github.com/stephane/libmodbus/issues/843", "creation_timestamp": "2026-07-09T03:42:07.101466Z"} 2026-07-09T03:42:07.101466+00:00