{"schemaVersion":3,"id":"CVE-2020-27738","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"A vulnerability has been identified in APOGEE PXC Compact (BACnet) (All versions < V3.5.5), APOGEE PXC Compact (P2 Ethernet) (All versions < V2.8.20), APOGEE PXC Modular (BACnet) (All versions < V3.5.5), APOGEE PXC Modular (P2 Ethernet) (All versions < V2.8.20), Nucleus NET (All versions), Nucleus ReadyStart V3 (All versions < V2017.02.3), Nucleus ReadyStart V4 (All versions < V4.1.0), Nucleus Source Code (Versions including affected DNS modules), SIMOTICS CONNECT 400 (All versions < V0.5.0.0), TALON TC Compact (BACnet) (All versions < V3.5.5), TALON TC Modular (BACnet) (All versions < V3.5.5). The DNS domain name record decompression functionality does not properly validate the pointer offset values. The parsing of malformed responses could result in a read access past the end of an allocated structure. An attacker with a privileged position in the network could leverage this vulnerability to cause a denial-of-service condition.","dates":{"published":"2021-04-22T20:42:20.000Z","modified":"2024-08-04T16:18:45.774Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":7.4,"severity":"high","version":"3.1","versionLabel":"v3.1","source":"NVD","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":6.5,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H/E:P/RL:O/RC:C","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":7.4,"severity":"high","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H","exploitability":null,"impact":null,"computed":false},{"version":"2.0","versionLabel":"v2.0","source":"NVD","score":5.8,"severity":"medium","vector":"AV:N/AC:M/Au:N/C:P/I:N/A:P","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.03659,"percentile":0.89478,"severity":"low","asOf":"2026-10-18T00:00:00.000Z","change":{"pp":0,"baselineDate":"2026-09-18T00:00:00.000Z","baselineScore":0.03659},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.03659,"percentile":0.89478}],"last30":[{"date":"2026-09-18T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.03659,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.03659,"percentile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