CVE intelligence and bounded remediation

CVE-2023-20047 — Cisco Webex Room Phone Firmware security vulnerability

Medium CVSS 6.5

A vulnerability in the Link Layer Discovery Protocol (LLDP) feature of Cisco Webex Room Phone and Cisco Webex Share devices could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient resource allocation. An attacker could exploit this vulnerability by sending crafted LLDP traffic to an affected device. A successful exploit could allow the attacker to exhaust the memory resources of the affected device, resulting in a crash of the LLDP process. If the affected device is configured to support LLDP only, this could cause an interruption to inbound and outbound calling. By default, these devices are configured to support both Cisco Discovery Protocol and LLDP. To recover operational state, the affected device needs a manual restart.

Severity
Medium
CVSS
6.5 (3.1)
Published
2023-01-20
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-400, CWE-770

Affected products

  • cisco / webex_room_phone_firmware
  • cisco / webex_share_firmware
  • cisco / sip_ip_phone_software

Matched remediation archetype

Resource exhaustion and denial of service

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify attacker-influenced work factors including input size, nesting, compression, fan-out, regex cost, allocation, recursion, retries, and connection lifetime.
  • Map per-request and shared CPU, memory, disk, descriptor, thread, queue, and downstream-service limits.
  • Determine whether authentication, tenancy, quotas, and rate controls apply before expensive processing begins.

Remediate safely

  • Bound input size, nesting, expansion, work, concurrency, queue depth, retries, and execution time before resource-intensive processing.
  • Release resources on every success, error, cancellation, and timeout path and use backpressure instead of unbounded buffering.
  • Update affected components and add small deterministic tests that assert resource ceilings rather than exhausting a host.

Authoritative sources

Complete CVE record and remediation plan

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