CVE-2026-20211 (GCVE-0-2026-20211)
Vulnerability from cvelistv5
Published
2026-09-16 20:04
Modified
2026-09-17 11:39
Severity ?
9.1 (Critical) - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
CWE
  • CWE-502 - Deserialization of Untrusted Data
Summary
A vulnerability in Cisco ISE could allow an authenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected device. To exploit this vulnerability, the attacker must have valid high-privileged administrative credentials. This vulnerability is due to insecure deserialization of Java objects by the affected software. An attacker could exploit this vulnerability by sending a crafted serialized Java object to an affected device. A successful exploit could allow the attacker to obtain user-level access to the underlying operating system and then elevate privileges to root. In single-node deployments, successful exploitation of this vulnerability could cause the affected ISE node to become unavailable, resulting in a DoS condition. In that condition, endpoints that have not already authenticated would be unable to access the network until the node is restored.
References
Impacted products
Vendor Product Version
Cisco Cisco Identity Services Engine Software Version: 3.1.0
Version: 3.1.0 p1
Version: 3.1.0 p3
Version: 3.1.0 p2
Version: 3.2.0
Version: 3.1.0 p4
Version: 3.1.0 p5
Version: 3.2.0 p1
Version: 3.1.0 p6
Version: 3.2.0 p2
Version: 3.1.0 p7
Version: 3.3.0
Version: 3.2.0 p3
Version: 3.2.0 p4
Version: 3.1.0 p8
Version: 3.2.0 p5
Version: 3.2.0 p6
Version: 3.1.0 p9
Version: 3.3 Patch 2
Version: 3.3 Patch 1
Version: 3.3 Patch 3
Version: 3.4.0
Version: 3.2.0 p7
Version: 3.3 Patch 4
Version: 3.4 Patch 1
Version: 3.1.0 p10
Version: 3.3 Patch 5
Version: 3.3 Patch 6
Version: 3.4 Patch 2
Version: 3.3 Patch 7
Version: 3.4 Patch 3
Version: 3.5.0
Version: 3.4 Patch 4
Version: 3.3 Patch 8
Version: 3.2 Patch 8
Version: 3.5 Patch 1
Version: 3.3 Patch 9
Version: 3.2 Patch 9
Version: 3.4 Patch 5
Version: 3.5 Patch 3
Version: 3.5 Patch 2
Version: 3.3 Patch 10
Version: 3.3 Patch 11
Version: 3.4 Patch 6
Version: 3.2 Patch 10
Version: 3.1.0 p72
Version: 3.1.0 p11
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-20211",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-17T03:57:12.101305Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-17T11:39:23.586Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unknown",
          "product": "Cisco Identity Services Engine Software",
          "vendor": "Cisco",
          "versions": [
            {
              "status": "affected",
              "version": "3.1.0"
            },
            {
              "status": "affected",
              "version": "3.1.0 p1"
            },
            {
              "status": "affected",
              "version": "3.1.0 p3"
            },
            {
              "status": "affected",
              "version": "3.1.0 p2"
            },
            {
              "status": "affected",
              "version": "3.2.0"
            },
            {
              "status": "affected",
              "version": "3.1.0 p4"
            },
            {
              "status": "affected",
              "version": "3.1.0 p5"
            },
            {
              "status": "affected",
              "version": "3.2.0 p1"
            },
            {
              "status": "affected",
              "version": "3.1.0 p6"
            },
            {
              "status": "affected",
              "version": "3.2.0 p2"
            },
            {
              "status": "affected",
              "version": "3.1.0 p7"
            },
            {
              "status": "affected",
              "version": "3.3.0"
            },
            {
              "status": "affected",
              "version": "3.2.0 p3"
            },
            {
              "status": "affected",
              "version": "3.2.0 p4"
            },
            {
              "status": "affected",
              "version": "3.1.0 p8"
            },
            {
              "status": "affected",
              "version": "3.2.0 p5"
            },
            {
              "status": "affected",
              "version": "3.2.0 p6"
            },
            {
              "status": "affected",
              "version": "3.1.0 p9"
            },
            {
              "status": "affected",
              "version": "3.3 Patch 2"
            },
            {
              "status": "affected",
              "version": "3.3 Patch 1"
            },
            {
              "status": "affected",
              "version": "3.3 Patch 3"
            },
            {
              "status": "affected",
              "version": "3.4.0"
            },
            {
              "status": "affected",
              "version": "3.2.0 p7"
            },
            {
              "status": "affected",
              "version": "3.3 Patch 4"
            },
            {
              "status": "affected",
              "version": "3.4 Patch 1"
            },
            {
              "status": "affected",
              "version": "3.1.0 p10"
            },
            {
              "status": "affected",
              "version": "3.3 Patch 5"
            },
            {
              "status": "affected",
              "version": "3.3 Patch 6"
            },
            {
              "status": "affected",
              "version": "3.4 Patch 2"
            },
            {
              "status": "affected",
              "version": "3.3 Patch 7"
            },
            {
              "status": "affected",
              "version": "3.4 Patch 3"
            },
            {
              "status": "affected",
              "version": "3.5.0"
            },
            {
              "status": "affected",
              "version": "3.4 Patch 4"
            },
            {
              "status": "affected",
              "version": "3.3 Patch 8"
            },
            {
              "status": "affected",
              "version": "3.2 Patch 8"
            },
            {
              "status": "affected",
              "version": "3.5 Patch 1"
            },
            {
              "status": "affected",
              "version": "3.3 Patch 9"
            },
            {
              "status": "affected",
              "version": "3.2 Patch 9"
            },
            {
              "status": "affected",
              "version": "3.4 Patch 5"
            },
            {
              "status": "affected",
              "version": "3.5 Patch 3"
            },
            {
              "status": "affected",
              "version": "3.5 Patch 2"
            },
            {
              "status": "affected",
              "version": "3.3 Patch 10"
            },
            {
              "status": "affected",
              "version": "3.3 Patch 11"
            },
            {
              "status": "affected",
              "version": "3.4 Patch 6"
            },
            {
              "status": "affected",
              "version": "3.2 Patch 10"
            },
            {
              "status": "affected",
              "version": "3.1.0 p72"
            },
            {
              "status": "affected",
              "version": "3.1.0 p11"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "A vulnerability in Cisco ISE could allow an authenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected device. To exploit this vulnerability, the attacker must have valid high-privileged administrative credentials.\r\n\r\nThis vulnerability is due to insecure deserialization of Java objects by the affected software. An attacker could exploit this vulnerability by sending a crafted serialized Java object to an affected device. A successful exploit could allow the attacker to obtain user-level access to the underlying operating system and then elevate privileges to\u0026nbsp;root. In single-node deployments, successful exploitation of this vulnerability could cause the affected ISE node to become unavailable, resulting in a DoS condition. In that condition, endpoints that have not already authenticated would be unable to access the network until the node is restored."
        }
      ],
      "exploits": [
        {
          "lang": "en",
          "value": "The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerabilities that are described in this advisory."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.1,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "HIGH",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
          },
          "format": "cvssV3_1"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-502",
              "description": "Deserialization of Untrusted Data",
              "lang": "en",
              "type": "cwe"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-16T20:04:10.340Z",
        "orgId": "d1c1063e-7a18-46af-9102-31f8928bc633",
        "shortName": "cisco"
      },
      "references": [
        {
          "name": "cisco-sa-ise-rce-se7bYU57",
          "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-rce-se7bYU57"
        }
      ],
      "source": {
        "advisory": "cisco-sa-ise-rce-se7bYU57",
        "defects": [
          "CSCwu59400"
        ],
        "discovery": "EXTERNAL"
      },
      "title": "Cisco Identity Services Engine Remote Code Execution Vulnerability"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "d1c1063e-7a18-46af-9102-31f8928bc633",
    "assignerShortName": "cisco",
    "cveId": "CVE-2026-20211",
    "datePublished": "2026-09-16T20:04:10.340Z",
    "dateReserved": "2025-10-08T11:59:15.398Z",
    "dateUpdated": "2026-09-17T11:39:23.586Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "vulnrichment": {
      "containers": "{\"cna\": {\"title\": \"Cisco Identity Services Engine Remote Code Execution Vulnerability\", \"source\": {\"defects\": [\"CSCwu59400\"], \"advisory\": \"cisco-sa-ise-rce-se7bYU57\", \"discovery\": \"EXTERNAL\"}, \"metrics\": [{\"format\": \"cvssV3_1\", \"cvssV3_1\": {\"scope\": \"CHANGED\", \"version\": \"3.1\", \"baseScore\": 9.1, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"CRITICAL\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"HIGH\", \"confidentialityImpact\": \"HIGH\"}}], \"affected\": [{\"vendor\": \"Cisco\", \"product\": \"Cisco Identity Services Engine Software\", \"versions\": [{\"status\": \"affected\", \"version\": \"3.1.0\"}, {\"status\": \"affected\", \"version\": \"3.1.0 p1\"}, {\"status\": \"affected\", \"version\": \"3.1.0 p3\"}, {\"status\": \"affected\", \"version\": \"3.1.0 p2\"}, {\"status\": \"affected\", \"version\": \"3.2.0\"}, {\"status\": \"affected\", \"version\": \"3.1.0 p4\"}, {\"status\": \"affected\", \"version\": \"3.1.0 p5\"}, {\"status\": \"affected\", \"version\": \"3.2.0 p1\"}, {\"status\": \"affected\", \"version\": \"3.1.0 p6\"}, {\"status\": \"affected\", \"version\": \"3.2.0 p2\"}, {\"status\": \"affected\", \"version\": \"3.1.0 p7\"}, {\"status\": \"affected\", \"version\": \"3.3.0\"}, {\"status\": \"affected\", \"version\": \"3.2.0 p3\"}, {\"status\": \"affected\", \"version\": \"3.2.0 p4\"}, {\"status\": \"affected\", \"version\": \"3.1.0 p8\"}, {\"status\": \"affected\", \"version\": \"3.2.0 p5\"}, {\"status\": \"affected\", \"version\": \"3.2.0 p6\"}, {\"status\": \"affected\", \"version\": \"3.1.0 p9\"}, {\"status\": \"affected\", \"version\": \"3.3 Patch 2\"}, {\"status\": \"affected\", \"version\": \"3.3 Patch 1\"}, {\"status\": \"affected\", \"version\": \"3.3 Patch 3\"}, {\"status\": \"affected\", \"version\": \"3.4.0\"}, {\"status\": \"affected\", \"version\": \"3.2.0 p7\"}, {\"status\": \"affected\", \"version\": \"3.3 Patch 4\"}, {\"status\": \"affected\", \"version\": \"3.4 Patch 1\"}, {\"status\": \"affected\", \"version\": \"3.1.0 p10\"}, {\"status\": \"affected\", \"version\": \"3.3 Patch 5\"}, {\"status\": \"affected\", \"version\": \"3.3 Patch 6\"}, {\"status\": \"affected\", \"version\": \"3.4 Patch 2\"}, {\"status\": \"affected\", \"version\": \"3.3 Patch 7\"}, {\"status\": \"affected\", \"version\": \"3.4 Patch 3\"}, {\"status\": \"affected\", \"version\": \"3.5.0\"}, {\"status\": \"affected\", \"version\": \"3.4 Patch 4\"}, {\"status\": \"affected\", \"version\": \"3.3 Patch 8\"}, {\"status\": \"affected\", \"version\": \"3.2 Patch 8\"}, {\"status\": \"affected\", \"version\": \"3.5 Patch 1\"}, {\"status\": \"affected\", \"version\": \"3.3 Patch 9\"}, {\"status\": \"affected\", \"version\": \"3.2 Patch 9\"}, {\"status\": \"affected\", \"version\": \"3.4 Patch 5\"}, {\"status\": \"affected\", \"version\": \"3.5 Patch 3\"}, {\"status\": \"affected\", \"version\": \"3.5 Patch 2\"}, {\"status\": \"affected\", \"version\": \"3.3 Patch 10\"}, {\"status\": \"affected\", \"version\": \"3.3 Patch 11\"}, {\"status\": \"affected\", \"version\": \"3.4 Patch 6\"}, {\"status\": \"affected\", \"version\": \"3.2 Patch 10\"}, {\"status\": \"affected\", \"version\": \"3.1.0 p72\"}, {\"status\": \"affected\", \"version\": \"3.1.0 p11\"}], \"defaultStatus\": \"unknown\"}], \"exploits\": [{\"lang\": \"en\", \"value\": \"The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerabilities that are described in this advisory.\"}], \"references\": [{\"url\": \"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-rce-se7bYU57\", \"name\": \"cisco-sa-ise-rce-se7bYU57\"}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"A vulnerability in Cisco ISE could allow an authenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected device. To exploit this vulnerability, the attacker must have valid high-privileged administrative credentials.\\r\\n\\r\\nThis vulnerability is due to insecure deserialization of Java objects by the affected software. An attacker could exploit this vulnerability by sending a crafted serialized Java object to an affected device. A successful exploit could allow the attacker to obtain user-level access to the underlying operating system and then elevate privileges to\u0026nbsp;root. In single-node deployments, successful exploitation of this vulnerability could cause the affected ISE node to become unavailable, resulting in a DoS condition. In that condition, endpoints that have not already authenticated would be unable to access the network until the node is restored.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"cwe\", \"cweId\": \"CWE-502\", \"description\": \"Deserialization of Untrusted Data\"}]}], \"providerMetadata\": {\"orgId\": \"d1c1063e-7a18-46af-9102-31f8928bc633\", \"shortName\": \"cisco\", \"dateUpdated\": \"2026-09-16T20:04:10.340Z\"}}, \"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-20211\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-09-17T03:57:12.101305Z\"}}}], \"providerMetadata\": {\"shortName\": \"CISA-ADP\", \"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"dateUpdated\": \"2026-09-17T11:31:59.704Z\"}}]}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-20211\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-09-16T20:04:10.340Z\", \"dateReserved\": \"2025-10-08T11:59:15.398Z\", \"assignerOrgId\": \"d1c1063e-7a18-46af-9102-31f8928bc633\", \"datePublished\": \"2026-09-16T20:04:10.340Z\", \"assignerShortName\": \"cisco\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.