CVE-2021-42567 (GCVE-0-2021-42567)

Vulnerability from cvelistv5 – Published: 2021-12-07 21:10 – Updated: 2024-08-04 03:38
VLAI Previdian
Summary
Apereo CAS through 6.4.1 allows XSS via POST requests sent to the REST API endpoints.
Severity
6.1 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CWE
  • n/a
Assigner
References
Previdian
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: 00014b15-ac6d-41f2-9966-ae605c31a9f6

Vulnerability ID: CVE-2021-42567

Status: Confirmed

Status Updated: 2021-12-07 22:10 CET

Exploited: Yes

Timestamps
First Seen: 2021-12-07
Asserted: 2021-12-07
Scope
Notes: Apereo CAS through 6.4.1 allows XSS via POST requests sent to the REST API endpoints. | Affected: Apereo / CAS | CVSS: 6.1 (MEDIUM) | EPSS: 0.08191 | Used in malware: unknown | Not yet in CISA KEV: True
Evidence

Type: Public Report

Signal: Successful Exploitation

Confidence: 70%

Source: previdian

Details
Feed Previdian (previdian.com)
Title Apereo CAS through 6.4.1 allows XSS via POST requests sent to the REST API endpoints.
Cve Id CVE-2021-42567
Vendor Apereo
Ghsa Id GHSA-GFHX-JJWQ-63GV
Product CAS
Added Date 2021-12-07T21:10:49.000Z
Cvss Score 6.1
Epss Score 0.08191
Previous Ids
Cvss Severity MEDIUM
Virtual Patch False
Cvss Estimated False
Epss Percentile 0.94706
Used In Malware unknown
Vulnerability Id CVE-2021-42567
Ahead Of Cisa Kev None
Not Yet In Cisa Kev True
References
Created: 2026-10-02 09:11 CEST | Updated: 2026-10-02 09:11 CEST
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-04T03:38:49.276Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://github.com/apereo/cas/releases"
          },
          {
            "tags": [
              "x_refsource_CONFIRM",
              "x_transferred"
            ],
            "url": "https://apereo.github.io/2021/10/18/restvuln/"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Apereo CAS through 6.4.1 allows XSS via POST requests sent to the REST API endpoints."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "n/a",
              "lang": "en",
              "type": "text"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2021-12-07T21:10:49.000Z",
        "orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
        "shortName": "mitre"
      },
      "references": [
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/apereo/cas/releases"
        },
        {
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://apereo.github.io/2021/10/18/restvuln/"
        }
      ],
      "x_legacyV4Record": {
        "CVE_data_meta": {
          "ASSIGNER": "cve@mitre.org",
          "ID": "CVE-2021-42567",
          "STATE": "PUBLIC"
        },
        "affects": {
          "vendor": {
            "vendor_data": [
              {
                "product": {
                  "product_data": [
                    {
                      "product_name": "n/a",
                      "version": {
                        "version_data": [
                          {
                            "version_value": "n/a"
                          }
                        ]
                      }
                    }
                  ]
                },
                "vendor_name": "n/a"
              }
            ]
          }
        },
        "data_format": "MITRE",
        "data_type": "CVE",
        "data_version": "4.0",
        "description": {
          "description_data": [
            {
              "lang": "eng",
              "value": "Apereo CAS through 6.4.1 allows XSS via POST requests sent to the REST API endpoints."
            }
          ]
        },
        "problemtype": {
          "problemtype_data": [
            {
              "description": [
                {
                  "lang": "eng",
                  "value": "n/a"
                }
              ]
            }
          ]
        },
        "references": {
          "reference_data": [
            {
              "name": "https://github.com/apereo/cas/releases",
              "refsource": "MISC",
              "url": "https://github.com/apereo/cas/releases"
            },
            {
              "name": "https://apereo.github.io/2021/10/18/restvuln/",
              "refsource": "CONFIRM",
              "url": "https://apereo.github.io/2021/10/18/restvuln/"
            }
          ]
        }
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
    "assignerShortName": "mitre",
    "cveId": "CVE-2021-42567",
    "datePublished": "2021-12-07T21:10:49.000Z",
    "dateReserved": "2021-10-18T00:00:00.000Z",
    "dateUpdated": "2024-08-04T03:38:49.276Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2021-42567",
      "date": "2026-10-02",
      "epss": "0.08191",
      "percentile": "0.94709"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "product": "n/a",
                "vendor": "n/a",
                "versions": [
                  {
                    "status": "affected",
                    "version": "n/a"
                  }
                ]
              }
            ],
            "source": "cve@mitre.org"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:a:apereo:central_authentication_service:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "1E0AE631-B3F1-4F01-B70A-F1099DB4C976",
                    "versionEndExcluding": "6.3.7.1",
                    "versionStartIncluding": "6.3.0",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:a:apereo:central_authentication_service:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "29A88276-77E2-4EF9-8823-42E02AF0E1E3",
                    "versionEndExcluding": "6.4.2",
                    "versionStartIncluding": "6.4.0",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "Apereo CAS through 6.4.1 allows XSS via POST requests sent to the REST API endpoints."
          },
          {
            "lang": "es",
            "value": "Apereo CAS versiones hasta 6.4.1, permite un ataque de tipo XSS por medio de peticiones POST enviadas a los endpoints de la API REST"
          }
        ],
        "id": "CVE-2021-42567",
        "lastModified": "2026-06-17T04:09:50.740",
        "metrics": {
          "cvssMetricV2": [
            {
              "acInsufInfo": false,
              "baseSeverity": "MEDIUM",
              "cvssData": {
                "accessComplexity": "MEDIUM",
                "accessVector": "NETWORK",
                "authentication": "NONE",
                "availabilityImpact": "NONE",
                "baseScore": 4.3,
                "confidentialityImpact": "NONE",
                "integrityImpact": "PARTIAL",
                "vectorString": "AV:N/AC:M/Au:N/C:N/I:P/A:N",
                "version": "2.0"
              },
              "exploitabilityScore": 8.6,
              "impactScore": 2.9,
              "obtainAllPrivilege": false,
              "obtainOtherPrivilege": false,
              "obtainUserPrivilege": false,
              "source": "nvd@nist.gov",
              "type": "Primary",
              "userInteractionRequired": true
            }
          ],
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "NONE",
                "baseScore": 6.1,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "LOW",
                "integrityImpact": "LOW",
                "privilegesRequired": "NONE",
                "scope": "CHANGED",
                "userInteraction": "REQUIRED",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
                "version": "3.1"
              },
              "exploitabilityScore": 2.8,
              "impactScore": 2.7,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ]
        },
        "published": "2021-12-07T22:15:06.907",
        "references": [
          {
            "source": "cve@mitre.org",
            "tags": [
              "Patch",
              "Third Party Advisory"
            ],
            "url": "https://apereo.github.io/2021/10/18/restvuln/"
          },
          {
            "source": "cve@mitre.org",
            "tags": [
              "Release Notes",
              "Third Party Advisory"
            ],
            "url": "https://github.com/apereo/cas/releases"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch",
              "Third Party Advisory"
            ],
            "url": "https://apereo.github.io/2021/10/18/restvuln/"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Release Notes",
              "Third Party Advisory"
            ],
            "url": "https://github.com/apereo/cas/releases"
          }
        ],
        "sourceIdentifier": "cve@mitre.org",
        "vulnStatus": "Modified",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-79"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.