Multiple vulnerabilities in the Cisco Discovery Protocol and Link Layer Discovery Protocol (LLDP) implementations for Cisco 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. These vulnerabilities are due to missing checks when the IP phone processes a Cisco Discovery Protocol or LLDP packet. An attacker could exploit these vulnerabilities by sending a malicious Cisco 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 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 has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities.
Use CWE-120, Cisco vendor hub and Ip Conference Phone 7832 Firmware product page to widen CVE-2021-1379 into its surrounding weakness, vendor, and product context.
Compare it with CVE-2020-3111, CVE-2019-1635 and CVE-2019-1684 for nearby disclosures in the same product family. Additional editorial context is available in The Weekly Cybersecurity Brief: January 30th, 2026.