{"id":"CVE-2021-31889","aliases":["A-207646334","A-207646335","A-207646336","ASB-A-207646334","ASB-A-207646335","ASB-A-207646336","EUVD-2021-18764","GHSA-9f8q-4pw9-8433","M-MOLY00756840"],"status":"published","title":"A vulnerability has been identified in APOGEE MBC (PPC) (BACnet) (All versions), APOGEE MBC (PPC)...","description":"A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All versions), Capital Embedded AR Classic R20-11 (All versions \u003c V2303), PLUSCONTROL 1st Gen (All versions), SIMOTICS CONNECT 400 (All versions \u003c V0.5.0.0). Malformed TCP packets with a corrupted SACK option leads to Information Leaks and Denial-of-Service conditions. (FSMD-2021-0015)","severity":{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.02175,"percentile":0.82581,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-191"],"published":"2021-11-09T11:32:01Z","modified":"2026-11-05T16:32:28Z","affected":[{"source":"osv","ecosystem":"Android","package":":unknown:","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"SoCVersion:0"},{"fixed":"SoCVersion:2022-01-05"}]}],"versions":["SoCVersion"],"bundled":3},{"source":"osv","ecosystem":"Android","package":":unknown:","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"SoCVersion:0"},{"fixed":"SoCVersion:2022-01-05"}]}],"versions":["SoCVersion"],"bundled":3},{"source":"osv","ecosystem":"Android","package":":unknown:","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"SoCVersion:0"},{"fixed":"SoCVersion:2022-01-05"}]}],"versions":["SoCVersion"],"bundled":3}],"products":[{"vendor":"siemens","product":"apogee_modular_building_controller_firmware"},{"vendor":"siemens","product":"apogee_modular_equiment_controller_firmware"},{"vendor":"siemens","product":"apogee_pxc_compact_firmware"},{"vendor":"siemens","product":"apogee_pxc_modular_firmware"},{"vendor":"siemens","product":"capital embedded ar classic 431-422"},{"vendor":"siemens","product":"capital embedded ar classic r20-11"},{"vendor":"siemens","product":"capital_vstar"},{"vendor":"siemens","product":"nucleus_net"},{"vendor":"siemens","product":"nucleus_readystart_v3"},{"vendor":"siemens","product":"nucleus_source_code"},{"vendor":"siemens","product":"pluscontrol 1st gen"},{"vendor":"siemens","product":"simotics connect 400"},{"vendor":"siemens","product":"talon_tc_compact_firmware"},{"vendor":"siemens","product":"talon_tc_modular_firmware"}],"references":[{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-114589.pdf","tags":["x_refsource_MISC","x_transferred","Vendor Advisory"]},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-044112.pdf","tags":["x_refsource_MISC","x_transferred","Vendor Advisory"]},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-620288.pdf","tags":["x_refsource_MISC","x_transferred"]},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-845392.pdf","tags":["x_refsource_MISC","x_transferred"]},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-223353.pdf","tags":["x_refsource_MISC","x_transferred"]},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-114589.html"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-044112.html"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-620288.html"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-845392.html"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-223353.html"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-31889"},{"url":"https://github.com/advisories/GHSA-9f8q-4pw9-8433"},{"url":"https://source.android.com/security/bulletin/2022-01-01","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2021-31889","description":"A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All versions), Capital Embedded AR Classic R20-11 (All versions \u003c V2303), PLUSCONTROL 1st Gen (All versions), SIMOTICS CONNECT 400 (All versions \u003c V0.5.0.0). Malformed TCP packets with a corrupted SACK option leads to Information Leaks and Denial-of-Service conditions. (FSMD-2021-0015)","status":"published","published":"2021-11-09T11:32:01Z","modified":"2025-03-11T09:47:45.226Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-191"],"updated_at":"2026-11-02T14:33:05.989686Z"}],"euvd":[{"id":"EUVD-2021-18764","description":"A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All versions), Capital Embedded AR Classic R20-11 (All versions \u003c V2303), PLUSCONTROL 1st Gen (All versions), SIMOTICS CONNECT 400 (All versions \u003c V0.5.0.0). Malformed TCP packets with a corrupted SACK option leads to Information Leaks and Denial-of-Service conditions. (FSMD-2021-0015)","status":"published","published":"2021-11-09T11:32:01Z","modified":"2025-03-11T09:47:45Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T20:53:08.182954Z"}],"ghsa":[{"id":"GHSA-9f8q-4pw9-8433","title":"A vulnerability has been identified in APOGEE MBC (PPC) (BACnet) (All versions), APOGEE MBC (PPC)...","description":"A vulnerability has been identified in APOGEE MBC (PPC) (BACnet) (All versions), APOGEE MBC (PPC) (P2 Ethernet) (All versions), APOGEE MEC (PPC) (BACnet) (All versions), APOGEE MEC (PPC) (P2 Ethernet) (All versions), APOGEE PXC Compact (BACnet) (All versions), APOGEE PXC Compact (P2 Ethernet) (All versions), APOGEE PXC Modular (BACnet) (All versions), APOGEE PXC Modular (P2 Ethernet) (All versions), Capital VSTAR (All versions), Nucleus NET (All versions), Nucleus ReadyStart V3 (All versions \u003c V2017.02.4), Nucleus Source Code (All versions), TALON TC Compact (BACnet) (All versions), TALON TC Modular (BACnet) (All versions). Malformed TCP packets with a corrupted SACK option leads to Information Leaks and Denial-of-Service conditions. (FSMD-2021-0015)","status":"published","published":"2022-05-24T19:20:10Z","modified":"2024-10-08T09:30:51Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","level":"critical"}],"cwes":["CWE-191"],"updated_at":"2026-11-02T14:58:26.306971Z"}],"nvd":[{"id":"CVE-2021-31889","description":"A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All versions), Capital Embedded AR Classic R20-11 (All versions \u003c V2303), PLUSCONTROL 1st Gen (All versions), SIMOTICS CONNECT 400 (All versions \u003c V0.5.0.0). Malformed TCP packets with a corrupted SACK option leads to Information Leaks and Denial-of-Service conditions. (FSMD-2021-0015)","status":"published","published":"2021-11-09T12:15:09.693Z","modified":"2026-06-17T03:52:25.917Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"secondary"},{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","level":"critical","assessor":"primary"},{"version":"2.0","score":6.4,"vector":"AV:N/AC:L/Au:N/C:P/I:N/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-191"],"updated_at":"2026-11-02T14:07:00.984108Z"}],"osv":[{"id":"ASB-A-207646334","description":"In Modem ICMP protocol integrated from Nucleus NET TCP/IP software, there is a possible out of bounds write due to a missing bounds check. This could lead to remote information disclosure or denial of service with no additional execution privileges needed. User interaction is not needed for exploitation.","status":"published","published":"2022-01-01T00:00:00Z","modified":"2026-11-09T16:40:10.884737887Z","updated_at":"2026-11-10T17:35:05.376141Z"},{"id":"ASB-A-207646335","description":"In Modem TCP protocol integrated from Nucleus NET TCP/IP software, there is a possible system crash due to an improper input validation. This could lead to remote denial of service with no additional execution privileges needed. User interaction is not needed for exploitation.","status":"published","published":"2022-01-01T00:00:00Z","modified":"2026-11-10T17:02:23.040266809Z","updated_at":"2026-11-10T17:35:05.376141Z"},{"id":"ASB-A-207646336","description":"In Modem TCP protocol integrated from Nucleus NET TCP/IP software, there is a possible out of bounds write due to a missing bounds check. This could lead to remote information disclosure or denial of service with no additional execution privileges needed. User interaction is not needed for exploitation.","status":"published","published":"2022-01-01T00:00:00Z","modified":"2026-11-10T17:02:23.040266809Z","updated_at":"2026-11-09T17:04:22.742827Z"}]}}