CVE-2020-3161

Cisco IP Phones Web Server Remote Code Execution and Denial-of-Service

9.8 CRITICALActively exploited (CISA KEV)Public exploitEPSS 83.9%

Published15 Apr 2020
Added to CISA KEV3 Nov 2021
Remediation due3 May 2022

Description

A vulnerability in the web server for Cisco IP Phones could allow an unauthenticated, remote attacker to execute code with root privileges or cause a reload of an affected IP phone, resulting in a denial of service (DoS) condition. The vulnerability is due to a lack of proper input validation of HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to the web server of a targeted device. A successful exploit could allow the attacker to remotely execute code with root privileges or cause a reload of an affected IP phone, resulting in a DoS condition.

CVSS 3.1 breakdown

Attack vectorNetwork

Attack complexityLow

Privileges requiredNone

User interactionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

Cisco 8831 Firmware10.3\(1\)es14 · 11.0\(1\) · 11.0\(5\)sr1

Cisco Ip Phone 7811 Firmware11.0\(1\)

Cisco Ip Phone 7821 Firmware11.0\(1\)

Cisco Ip Phone 7841 Firmware11.0\(1\)

Cisco Ip Phone 7861 Firmware11.0\(1\)

Cisco Ip Phone 8811 Firmware10.3\(1\)es14 · 11.0\(1\) · 11.0\(5\)sr1

Cisco Ip Phone 8821-ex Firmware10.3\(1\)es14 · 11.0\(1\) · 11.0\(5\)sr1

Cisco Ip Phone 8821 Firmware10.3\(1\)es14 · 11.0\(1\) · 11.0\(5\)sr1

Cisco Ip Phone 8841 Firmware10.3\(1\)es14 · 11.0\(1\) · 11.0\(5\)sr1

Cisco Ip Phone 8845 Firmware10.3\(1\)es14 · 11.0\(1\) · 11.0\(5\)sr1

Cisco Ip Phone 8851 Firmware10.3\(1\)es14 · 11.0\(1\) · 11.0\(5\)sr1

Cisco Ip Phone 8861 Firmware10.3\(1\)es14 · 11.0\(1\) · 11.0\(5\)sr1

Cisco Ip Phone 8865 Firmware10.3\(1\)es14 · 11.0\(1\) · 11.0\(5\)sr1

Remediation

No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.

Patch & vendor advisories

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-voip-phones-rce-dos-rB6EeRXs

References

http://packetstormsecurity.com/files/157265/Cisco-IP-Phone-11.7-Denial-Of-Service.htmlExploitThird Party AdvisoryVDB Entry
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-voip-phones-rce-dos-rB6EeRXsVendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-3161US Government Resource

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

Frequently asked

Is CVE-2020-3161 being actively exploited?

Yes. CVE-2020-3161 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added 3 Nov 2021.

How severe is CVE-2020-3161?

CVE-2020-3161 has a CVSS 3.1 base score of 9.8, rated critical. EPSS estimates a 83.9% probability of exploitation.

Which products are affected by CVE-2020-3161?

Affected products include Cisco 8831 Firmware, Cisco Ip Phone 7811 Firmware, Cisco Ip Phone 7821 Firmware, Cisco Ip Phone 7841 Firmware, Cisco Ip Phone 7861 Firmware, and 8 more.

How do I fix CVE-2020-3161?

Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2020-3161 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. Because it is on the CISA KEV list, Secuno flags any affected asset as top-priority automatically. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

See how prioritisation works Book a demo

Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.