CASCACascade Atlas

Evidence dossier

CVE-2020-3161

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

82.8–98.3Priority evidence range
As known Jul 19, 2026, 5:00 AM UTCgen-56ccdaf9

Normalized restatement

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.

State
PUBLISHED
Published
Apr 15, 2020
Updated
Oct 21, 2025
Evidence coverage
72%
CISA KEVCatalog member

Apply updates per vendor instructions.

FIRST EPSS83.73%

2026-07-18 · v2026.06.15 · percentile 99.7%

Source stateConflict visible

Distinct CVSS assessments remain side by side; none are averaged.

Source comparison

Who said what

CISA-ADPindependent enrichment
container

CISA ADP Vulnrichment

ciscooriginal assertion
container

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

CVEderivative copy
container

CVE Program Container

CISA KEVoriginal assertion
observed_exploitation

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

FIRST EPSSoriginal assertion
model_probability

Probability 0.837340000000; percentile 0.996580000000

Applicability

Cited product scope

Trace impact →
CiscoCisco IP phone
[{"status": "affected", "version": "n/a"}]unknown
Unknown vendorUnknown product
cpe:2.3:h:cisco:8831:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:h:cisco:ip_phone_7811:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:h:cisco:ip_phone_7821:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:h:cisco:ip_phone_7841:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:h:cisco:ip_phone_7861:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:h:cisco:ip_phone_8811:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:h:cisco:ip_phone_8821:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:h:cisco:ip_phone_8821-ex:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:h:cisco:ip_phone_8841:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:h:cisco:ip_phone_8845:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:h:cisco:ip_phone_8851:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:h:cisco:ip_phone_8861:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:h:cisco:ip_phone_8865:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:o:cisco:8831_firmware:10.3\(1\)es14:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:8831_firmware:11.0\(1\):*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:8831_firmware:11.0\(5\)sr1:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_7811_firmware:11.0\(1\):*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_7821_firmware:11.0\(1\):*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_7841_firmware:11.0\(1\):*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_7861_firmware:11.0\(1\):*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8811_firmware:10.3\(1\)es14:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8811_firmware:11.0\(1\):*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8811_firmware:11.0\(5\)sr1:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8821-ex_firmware:10.3\(1\)es14:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8821-ex_firmware:11.0\(1\):*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8821-ex_firmware:11.0\(5\)sr1:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8821_firmware:10.3\(1\)es14:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(1\):*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(5\)sr1:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8841_firmware:10.3\(1\)es14:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8841_firmware:11.0\(1\):*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8841_firmware:11.0\(5\)sr1:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8845_firmware:10.3\(1\)es14:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8845_firmware:11.0\(1\):*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8845_firmware:11.0\(5\)sr1:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8851_firmware:10.3\(1\)es14:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8851_firmware:11.0\(1\):*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8851_firmware:11.0\(5\)sr1:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8861_firmware:10.3\(1\)es14:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8861_firmware:11.0\(1\):*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8861_firmware:11.0\(5\)sr1:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8865_firmware:10.3\(1\)es14:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8865_firmware:11.0\(1\):*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:cisco:ip_phone_8865_firmware:11.0\(5\)sr1:*:*:*:*:*:*:*supported

Assessments

CVSS by origin

9.8
nvd@nist.govCVSS 3.1 · role PrimaryCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
10.0
nvd@nist.govCVSS 2.0 · role PrimaryAV:N/AC:L/Au:N/C:C/I:C/A:C
9.8
psirt@cisco.comCVSS 3.0 · role SecondaryCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8
ciscoCVSS 3.0 · role unknownCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Limitations and unknowns

  • KEV membership is authoritative for the catalog, not proof of exposure in any environment.
  • EPSS is a dated model probability and not an individual-environment prediction.
  • Affected or fixed status applies only to the exact cited product and version scope; unresolved scope remains unknown.
  • NVD-carried upstream facts remain derivative and are not independent corroboration.
  • Only NVD metrics validated under the generation-bound calculator are Public Priority eligible; direct CVE record metrics remain display-only.
  • NVD CVSS source eligibility is closed: NVD-authored, exact record-source, or registered same-CVE container origin; unmapped sources remain display-only.
  • Factor D is unknown in Public Core because no accepted canonical mapping-obligation ledger is present.
  • Core replay supports the active and immediately prior generation; retrospective valid-at replay is deferred.