Vulnerability-Lookup

GHSA-63PC-J336-8QQ4

Vulnerability from github – Published: 2026-05-06 18:30 – Updated: 2026-05-06 18:30

Details

A vulnerability in an identity management API endpoint of Cisco ISE could allow an unauthenticated, remote attacker to enumerate valid user accounts on an affected device.

This vulnerability exists because error messages are observed when the affected API endpoint is called. An attacker could exploit this vulnerability by sending a series of crafted requests to the affected endpoint and analyzing the differentiated responses. A successful exploit could allow the attacker to compile a list of valid usernames on an affected system.

Severity ?

5.3 (Medium)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-20195"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-204"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-06T17:16:21Z",
    "severity": "MODERATE"
  },
  "details": "A vulnerability in an identity management API endpoint of Cisco ISE could allow an unauthenticated, remote attacker to enumerate valid user accounts on an affected device.\n\nThis vulnerability exists because error messages are observed when the affected API endpoint is called. An attacker could exploit this vulnerability by sending a series of crafted requests to the affected endpoint and analyzing the differentiated responses. A successful exploit could allow the attacker to compile a list of valid usernames on an affected system.",
  "id": "GHSA-63pc-j336-8qq4",
  "modified": "2026-05-06T18:30:31Z",
  "published": "2026-05-06T18:30:31Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-20195"
    },
    {
      "type": "WEB",
      "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-unauth-bypass-uxjRXGpb"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-20195 (GCVE-0-2026-20195)

Vulnerability from cvelistv5 – Published: 2026-05-06 16:14 – Updated: 2026-05-06 17:48

Title

Cisco Identity Services Engine Observable Response Discrepancy Vulnerability

Summary

A vulnerability in an identity management API endpoint of Cisco ISE could allow an unauthenticated, remote attacker to enumerate valid user accounts on an affected device. This vulnerability exists because error messages are observed when the affected API endpoint is called. An attacker could exploit this vulnerability by sending a series of crafted requests to the affected endpoint and analyzing the differentiated responses. A successful exploit could allow the attacker to compile a list of valid usernames on an affected system.

Severity ?

5.3 (Medium)


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

CWE

CWE-204 - Observable Response Discrepancy

Assigner

cisco

References

URL

Tags

https://sec.cloudapps.cisco.com/security/center/c…

Impacted products

	Vendor	Product	Version
	Cisco	Cisco Identity Services Engine Software	Affected: 3.3.0 Affected: 3.3 Patch 2 Affected: 3.3 Patch 1 Affected: 3.3 Patch 3 Affected: 3.4.0 Affected: 3.3 Patch 4 Affected: 3.4 Patch 1 Affected: 3.3 Patch 5 Affected: 3.3 Patch 6 Affected: 3.4 Patch 2 Affected: 3.3 Patch 7 Affected: 3.4 Patch 3 Affected: 3.5.0 Affected: 3.4 Patch 4 Affected: 3.3 Patch 8 Affected: 3.5 Patch 1 Affected: 3.3 Patch 9 Affected: 3.4 Patch 5 Affected: 3.5 Patch 3 Affected: 3.5 Patch 2 Affected: 3.3 Patch 10

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JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-20195",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-06T17:34:47.638851Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-06T17:48:38.355Z",
          "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": [
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              "status": "affected",
              "version": "3.3.0"
            },
            {
              "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": "3.3 Patch 4"
            },
            {
              "status": "affected",
              "version": "3.4 Patch 1"
            },
            {
              "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"
            },
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              "status": "affected",
              "version": "3.4 Patch 3"
            },
            {
              "status": "affected",
              "version": "3.5.0"
            },
            {
              "status": "affected",
              "version": "3.4 Patch 4"
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              "version": "3.3 Patch 8"
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              "version": "3.5 Patch 3"
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              "status": "affected",
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              "status": "affected",
              "version": "3.3 Patch 10"
            }
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        }
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          "lang": "en",
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        }
      ],
      "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."
        }
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      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
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          ]
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      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-06T16:14:54.611Z",
        "orgId": "d1c1063e-7a18-46af-9102-31f8928bc633",
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      },
      "references": [
        {
          "name": "cisco-sa-ise-unauth-bypass-uxjRXGpb",
          "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-unauth-bypass-uxjRXGpb"
        }
      ],
      "source": {
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        "defects": [
          "CSCwr77445"
        ],
        "discovery": "EXTERNAL"
      },
      "title": "Cisco Identity Services Engine Observable Response Discrepancy Vulnerability"
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-63PC-J336-8QQ4

CVE-2026-20195 (GCVE-0-2026-20195)

Tags

Sightings

Nomenclature