---
id: CVE-2026-20282
title: "A vulnerability in Cisco ISE could allow an authenticated, remote attacker to obtain write access on the underlying operating system of an affected device.\r\n\r\nThis vulnerability is due to insufficient validation of user-supplied input"
summary: "A vulnerability in Cisco ISE could allow an authenticated, remote attacker to obtain write access on the underlying operating system of an affected device.\r\n\r\nThis vulnerability is due to insufficient validation of user-supplied input. A…"
severity: medium
cvss: 4.9
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N'
cwe:
  - CWE-641
vendor: Cisco
product: Cisco Identity Services Engine Software
affected:
  - identity_services_engine_software 3.1.0
  - identity_services_engine_software 3.1.0 p1
  - identity_services_engine_software 3.1.0 p3
  - identity_services_engine_software 3.1.0 p2
  - identity_services_engine_software 3.2.0
  - identity_services_engine_software 3.1.0 p4
  - identity_services_engine_software 3.1.0 p5
  - identity_services_engine_software 3.2.0 p1
  - identity_services_engine_software 3.1.0 p6
  - identity_services_engine_software 3.2.0 p2
  - identity_services_engine_software 3.1.0 p7
  - identity_services_engine_software 3.3.0
  - identity_services_engine_software 3.2.0 p3
  - identity_services_engine_software 3.2.0 p4
  - identity_services_engine_software 3.1.0 p8
  - identity_services_engine_software 3.2.0 p5
  - identity_services_engine_software 3.2.0 p6
  - identity_services_engine_software 3.1.0 p9
  - identity_services_engine_software 3.3 Patch 2
  - identity_services_engine_software 3.3 Patch 1
  - identity_services_engine_software 3.3 Patch 3
  - identity_services_engine_software 3.4.0
  - identity_services_engine_software 3.2.0 p7
  - identity_services_engine_software 3.3 Patch 4
  - identity_services_engine_software 3.4 Patch 1
  - identity_services_engine_software 3.1.0 p10
  - identity_services_engine_software 3.3 Patch 5
  - identity_services_engine_software 3.3 Patch 6
  - identity_services_engine_software 3.4 Patch 2
  - identity_services_engine_software 3.3 Patch 7
  - identity_services_engine_software 3.4 Patch 3
  - identity_services_engine_software 3.5.0
  - identity_services_engine_software 3.4 Patch 4
  - identity_services_engine_software 3.3 Patch 8
  - identity_services_engine_software 3.2 Patch 8
  - identity_services_engine_software 3.5 Patch 1
  - identity_services_engine_software 3.3 Patch 9
  - identity_services_engine_software 3.2 Patch 9
  - identity_services_engine_software 3.4 Patch 5
  - identity_services_engine_software 3.5 Patch 3
  - identity_services_engine_software 3.5 Patch 2
  - identity_services_engine_software 3.3 Patch 10
  - identity_services_engine_software 3.3 Patch 11
  - identity_services_engine_software 3.4 Patch 6
  - identity_services_engine_software 3.2 Patch 10
  - identity_services_engine_software 3.1.0 p72
  - identity_services_engine_software 3.1.0 p11
  - identity_services_engine_software 3.1.0 p12
  - identity_services_engine_software 3.2 Patch 11
published: '2026-09-16'
updated: '2026-09-22'
sourceUpdated: '2026-09-22T21:17:30.440'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-20282'
references:
  - url: >-
      https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-mult-vul-ymSsTLCc
    label: psirt@cisco.com
  - url: 'https://software.cisco.com'
tags:
  - nvd
  - cve.org
  - csaf
  - vendor-advisory
  - cisco
epss: 0.00556
epssPercentile: 0.4521
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-22T16:53:45.213648Z'
ingestedAt: '2026-09-16T16:37:52.198Z'
---

## Overview

A vulnerability in Cisco ISE could allow an authenticated, remote attacker to obtain write access on the underlying operating system of an affected device.

This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could allow the attacker to obtain write access to the underlying operating system.
To exploit this vulnerability, the attacker must have valid administrative credentials.
Note: For CVE-2026-20282, Cisco has assigned a Security Impact Rating (SIR) of High rather than Medium as the score indicates. The reason is that it is easy to get to root from the achieved privilege level.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **cisco-sa-ise-mult-vul-ymSsTLCc** · Cisco · affected: Cisco Identity Services Engine Software (48 versions) · updated 2026-09-16 · [advisory](https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-mult-vul-ymSsTLCc)