{"id":"CVE-2021-1379","aliases":["EUVD-2021-6846","GHSA-722m-4rr5-cvfh"],"status":"published","title":"Cisco IP Phones Cisco Discovery Protocol and Link Layer Discovery Protocol Remote Code Execution and Denial of Service Vulnerabilities","description":"Multiple vulnerabilities in the Cisco\u0026nbsp;Discovery Protocol and Link Layer Discovery Protocol (LLDP) implementations for Cisco\u0026nbsp;IP Phone Series 68xx/78xx/88xx could allow an unauthenticated, adjacent attacker to execute code remotely or cause a reload of an affected IP phone.\r\nThese vulnerabilities are due to missing checks when the IP phone processes a Cisco\u0026nbsp;Discovery Protocol or LLDP packet. An attacker could exploit these vulnerabilities by sending a malicious Cisco\u0026nbsp;Discovery Protocol or LLDP packet to the targeted IP phone. A successful exploit could allow the attacker to execute code on the affected IP phone or cause it to reload unexpectedly, resulting in a denial of service (DoS) condition.Note: Cisco\u0026nbsp;Discovery Protocol is a Layer 2 protocol. To exploit these vulnerabilities, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).Cisco\u0026nbsp;has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities.","severity":{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/RL:X/RC:X/E:X","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00328,"percentile":0.26158,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-120"],"published":"2024-11-18T15:42:00Z","modified":"2026-06-17T03:31:38Z","products":[{"vendor":"cisco","product":"cisco ip phones with multiplatform firmware"},{"vendor":"cisco","product":"cisco session initiation protocol (sip) software"},{"vendor":"cisco","product":"cisco small business ip phones"},{"vendor":"cisco","product":"ip_conference_phone_7832_firmware"},{"vendor":"cisco","product":"ip_conference_phone_7832_with_multiplatform_firmware"},{"vendor":"cisco","product":"ip_conference_phone_8832_firmware"},{"vendor":"cisco","product":"ip_conference_phone_8832_with_multiplatform_firmware"},{"vendor":"cisco","product":"ip_phone_6821_with_multiplatform_firmware"},{"vendor":"cisco","product":"ip_phone_6841_with_multiplatform_firmware"},{"vendor":"cisco","product":"ip_phone_6851_with_multiplatform_firmware"},{"vendor":"cisco","product":"ip_phone_6861_with_multiplatform_firmware"},{"vendor":"cisco","product":"ip_phone_6871_with_multiplatform_firmware"},{"vendor":"cisco","product":"ip_phone_7811_firmware"},{"vendor":"cisco","product":"ip_phone_7811_with_multiplatform_firmware"},{"vendor":"cisco","product":"ip_phone_7821_firmware"},{"vendor":"cisco","product":"ip_phone_7821_with_multiplatform_firmware"},{"vendor":"cisco","product":"ip_phone_7841_firmware"},{"vendor":"cisco","product":"ip_phone_7841_with_multiplatform_firmware"},{"vendor":"cisco","product":"ip_phone_7861_firmware"},{"vendor":"cisco","product":"ip_phone_7861_with_multiplatform_firmware"},{"vendor":"cisco","product":"ip_phone_8811_firmware"},{"vendor":"cisco","product":"ip_phone_8811_with_multiplatform_firmware"},{"vendor":"cisco","product":"ip_phone_8841_firmware"},{"vendor":"cisco","product":"ip_phone_8841_with_multiplatform_firmware"},{"vendor":"cisco","product":"ip_phone_8845_firmware"},{"vendor":"cisco","product":"ip_phone_8845_with_multiplatform_firmware"},{"vendor":"cisco","product":"ip_phone_8851_firmware"},{"vendor":"cisco","product":"ip_phone_8851_with_multiplatform_firmware"},{"vendor":"cisco","product":"ip_phone_8861_firmware"},{"vendor":"cisco","product":"ip_phone_8861_with_multiplatform_firmware"},{"vendor":"cisco","product":"ip_phone_8865_firmware"},{"vendor":"cisco","product":"ip_phone_8865_with_multiplatform_firmware"},{"vendor":"cisco","product":"spa525g_firmware"},{"vendor":"cisco","product":"unified_ip_conference_phone_8831_firmware"},{"vendor":"cisco","product":"unified_ip_conference_phone_8831_for_third-party_call_control_firmware"},{"vendor":"cisco","product":"wireless_ip_phone_8821-ex_firmware"},{"vendor":"cisco","product":"wireless_ip_phone_8821_firmware"}],"references":[{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ipphone-rce-dos-U2PsSkz3","tags":["Vendor Advisory"]},{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-webex-distupd-N87eB6Z3","tags":["Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-1379"},{"url":"https://github.com/advisories/GHSA-722m-4rr5-cvfh"}],"sources":{"cve":[{"id":"CVE-2021-1379","title":"Cisco IP Phones Cisco Discovery Protocol and Link Layer Discovery Protocol Remote Code Execution and Denial of Service Vulnerabilities","description":"Multiple vulnerabilities in the Cisco\u0026nbsp;Discovery Protocol and Link Layer Discovery Protocol (LLDP) implementations for Cisco\u0026nbsp;IP Phone Series 68xx/78xx/88xx could allow an unauthenticated, adjacent attacker to execute code remotely or cause a reload of an affected IP phone.\r\nThese vulnerabilities are due to missing checks when the IP phone processes a Cisco\u0026nbsp;Discovery Protocol or LLDP packet. An attacker could exploit these vulnerabilities by sending a malicious Cisco\u0026nbsp;Discovery Protocol or LLDP packet to the targeted IP phone. A successful exploit could allow the attacker to execute code on the affected IP phone or cause it to reload unexpectedly, resulting in a denial of service (DoS) condition.Note: Cisco\u0026nbsp;Discovery Protocol is a Layer 2 protocol. To exploit these vulnerabilities, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).Cisco\u0026nbsp;has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities.","status":"published","published":"2024-11-18T15:42:00.388Z","modified":"2024-11-18T16:23:13.534Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/RL:X/RC:X/E:X","level":"medium","assessor":"cna"}],"cwes":["CWE-120"],"updated_at":"2026-11-02T14:33:08.811269Z"}],"euvd":[{"id":"EUVD-2021-6846","description":"Multiple vulnerabilities in the Cisco\u0026nbsp;Discovery Protocol and Link Layer Discovery Protocol (LLDP) implementations for Cisco\u0026nbsp;IP Phone Series 68xx/78xx/88xx could allow an unauthenticated, adjacent attacker to execute code remotely or cause a reload of an affected IP phone.\r\nThese vulnerabilities are due to missing checks when the IP phone processes a Cisco\u0026nbsp;Discovery Protocol or LLDP packet. An attacker could exploit these vulnerabilities by sending a malicious Cisco\u0026nbsp;Discovery Protocol or LLDP packet to the targeted IP phone. A successful exploit could allow the attacker to execute code on the affected IP phone or cause it to reload unexpectedly, resulting in a denial of service (DoS) condition.Note: Cisco\u0026nbsp;Discovery Protocol is a Layer 2 protocol. To exploit these vulnerabilities, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).Cisco\u0026nbsp;has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities.","status":"published","published":"2024-11-18T15:42:00Z","modified":"2024-11-18T16:23:13Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/RL:X/RC:X/E:X","level":"medium"}],"updated_at":"2026-11-03T00:04:57.054288Z"}],"ghsa":[{"id":"GHSA-722m-4rr5-cvfh","title":"Multiple vulnerabilities in the Cisco\u0026nbsp;Discovery Protocol and Link Layer Discovery Protocol ...","description":"Multiple vulnerabilities in the Cisco\u0026nbsp;Discovery Protocol and Link Layer Discovery Protocol (LLDP) implementations for Cisco\u0026nbsp;IP Phone Series 68xx/78xx/88xx could allow an unauthenticated, adjacent attacker to execute code remotely or cause a reload of an affected IP phone.\nThese vulnerabilities are due to missing checks when the IP phone processes a Cisco\u0026nbsp;Discovery Protocol or LLDP packet. An attacker could exploit these vulnerabilities by sending a malicious Cisco\u0026nbsp;Discovery Protocol or LLDP packet to the targeted IP phone. A successful exploit could allow the attacker to execute code on the affected IP phone or cause it to reload unexpectedly, resulting in a denial of service (DoS) condition.Note: Cisco\u0026nbsp;Discovery Protocol is a Layer 2 protocol. To exploit these vulnerabilities, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).Cisco\u0026nbsp;has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities.","status":"published","published":"2024-11-18T18:30:57Z","modified":"2024-11-18T18:30:57Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-120"],"updated_at":"2026-11-02T14:58:52.476096Z"}],"nvd":[{"id":"CVE-2021-1379","description":"Multiple vulnerabilities in the Cisco\u0026nbsp;Discovery Protocol and Link Layer Discovery Protocol (LLDP) implementations for Cisco\u0026nbsp;IP Phone Series 68xx/78xx/88xx could allow an unauthenticated, adjacent attacker to execute code remotely or cause a reload of an affected IP phone.\r\nThese vulnerabilities are due to missing checks when the IP phone processes a Cisco\u0026nbsp;Discovery Protocol or LLDP packet. An attacker could exploit these vulnerabilities by sending a malicious Cisco\u0026nbsp;Discovery Protocol or LLDP packet to the targeted IP phone. A successful exploit could allow the attacker to execute code on the affected IP phone or cause it to reload unexpectedly, resulting in a denial of service (DoS) condition.Note: Cisco\u0026nbsp;Discovery Protocol is a Layer 2 protocol. To exploit these vulnerabilities, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).Cisco\u0026nbsp;has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities.","status":"published","published":"2024-11-18T16:15:09.31Z","modified":"2026-06-17T03:31:38.22Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"secondary"}],"cwes":["CWE-120"],"updated_at":"2026-11-02T14:07:08.629518Z"}]}}