Cyber Resilience

CVE-2023-20047

Medium

Published: 20 January 2023

Published
20 January 2023
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 6.5 CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0011 28.4th percentile
Risk Priority 13 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2023-20047 is a medium-severity Uncontrolled Resource Consumption (CWE-400) vulnerability in Cisco Webex Room Phone Firmware. Its CVSS base score is 6.5 (Medium).

Operationally, ranked at the 28.4th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

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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.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

cisco
webex room phone firmware
≤ 1.2.0
cisco
webex share firmware
≤ 1.2.0
cisco
sip ip phone software
≤ 1.2.0

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-400 CWE-770

Limiting concurrent sessions directly prevents uncontrolled resource consumption by capping the number of active sessions per user or account.

addresses: CWE-400 CWE-770

Contingency plan testing includes resource exhaustion scenarios to verify recovery, making it harder for attackers to sustain exploits that cause uncontrolled consumption.

addresses: CWE-400 CWE-770

Updated contingency plans include current procedures to detect, contain, and recover from resource exhaustion, limiting an attacker's ability to sustain impact from uncontrolled consumption.

addresses: CWE-400 CWE-770

Alternate site allows resumption of operations if resource exhaustion at the primary site is exploited to cause unavailability.

addresses: CWE-400 CWE-770

Alternate telecommunications services enable resumption of essential functions when primary services become unavailable due to uncontrolled resource consumption.

addresses: CWE-400 CWE-770

Planning and coordination of security activities (scans, tests, maintenance) directly imposes scheduling and throttling that prevents those activities from producing uncontrolled resource consumption.

addresses: CWE-400 CWE-770

Performance metrics and monitoring inherently track resource consumption patterns, making uncontrolled consumption easier to detect and mitigate.

addresses: CWE-400 CWE-770

Terminating idle connections bounds resource consumption that would otherwise allow uncontrolled accumulation of open sessions.

References