VulnTideExploited vulnerabilities, by vendor. Data as of 28 Oct 2026.
Known exploitedIn CISA's KEV catalog since 3 November 2021Ransomware use: unknown
Cisco Cisco IP Phones

CVE-2020-3161: Cisco IP Phones Web Server Remote Code Execution and Denial-of-Service Vulnerability

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 3 Nov 2021, 567 days after the CVE record was published.

How likely is exploitation in the next 30 days?
83.9%

EPSS score, percentile 99.7 of all scored records

How severe?
9.8 Critical

CVSS v3.0 base score, given by the CNA

What should I do?

CISA deadline 3 May 2022. Apply updates per vendor instructions.

Advisories and patches (1)

Which versions are affected?

Affected

  • unspecified

Versions by product

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

What to do

Required action, set by CISA

Apply updates per vendor instructions.

CISA due date for this action: 3 May 2022.

Advisories and patches

Linked from CISA's catalog entry

Affected products and versions

As listed in the CVE record.

Cisco Cisco IP phone
StatusVersions
Affectedunspecified

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

About this vulnerability

Cisco IP Phones contain an improper input validation vulnerability for HTTP requests. Exploitation could allow an attacker to execute code remotely with root privileges or cause a denial-of-service (DoS) condition.

Summary: CISA's KEV catalog, as of 28 Oct 2026.

  • CISA added CVE-2020-3161 to its Known Exploited Vulnerabilities (KEV) catalog on 3 Nov 2021.
  • CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
  • The due date CISA sets for the required action is 3 May 2022.
  • The CVE record was published on 15 Apr 2020, 567 days before it was added to KEV.
  • The CVE record carries a CVSS v3.0 base score of 9.8 (Critical), given by its CNA.
  • FIRST's EPSS model puts the probability of exploitation in the next 30 days at 83.9% (percentile 99.7), as of 28 Oct 2026.
  • CISA's SSVC assessment in the CVE record: exploitation active, automatable yes, technical impact total.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.

Description

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

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.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

Weakness

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.

Timeline

DateEvent
15 Apr 2020CVE record published
3 Nov 2021Added to CISA KEV
3 May 2022CISA due date for the required action
21 Oct 2025CVE record last updated

References

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