CVE-2021-1251

Multiple vulnerabilities exist in the Link Layer Discovery Protocol (LLDP) implementation for Cisco Small Business RV Series Routers. An unauthenticated, adjacent attacker could execute arbitrary code or cause an affected router to leak system memory or reload. A memory leak or device reload would cause a denial of service (DoS) condition on an affected device. For more information about these vulnerabilities, see the Details section of this advisory. Note: LLDP 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).

• CWE-119
• CWE-401

• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-rv-multi-lldp-u7e4chCeVendor Advisory
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-rv-multi-lldp-u7e4chCeVendor Advisory

Published

Apr 8, 2021

Last Modified

Jun 17, 2026

Status

Modified

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