Vulnerability-Lookup

ubuntu-cve-2021-21239

Vulnerability from osv_ubuntu

Published

2021-01-21 15:15

Modified

2025-09-08 16:46

Summary

Details

PySAML2 is a pure python implementation of SAML Version 2 Standard. PySAML2 before 6.5.0 has an improper verification of cryptographic signature vulnerability. Users of pysaml2 that use the default CryptoBackendXmlSec1 backend and need to verify signed SAML documents are impacted. PySAML2 does not ensure that a signed SAML document is correctly signed. The default CryptoBackendXmlSec1 backend is using the xmlsec1 binary to verify the signature of signed SAML documents, but by default xmlsec1 accepts any type of key found within the given document. xmlsec1 needs to be configured explicitly to only use only x509 certificates for the verification process of the SAML document signature. This is fixed in PySAML2 6.5.0.

Severity

6.5 (Medium)


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

6.5 (Medium)


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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2021-21239	REPORT
	https://github.com/IdentityPython/pysaml2/securit…	REPORT
	https://github.com/IdentityPython/pysaml2/release…	REPORT
	https://pypi.org/project/pysaml2	REPORT
	https://www.aleksey.com/pipermail/xmlsec/2013/009…	REPORT
	https://ubuntu.com/security/notices/USN-5066-1	ADVISORY
	https://ubuntu.com/security/notices/USN-5066-2	ADVISORY
	https://www.cve.org/CVERecord?id=CVE-2021-21239	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "python-pysaml2",
            "binary_version": "3.0.0-3ubuntu1.16.04.4+esm1"
          },
          {
            "binary_name": "python3-pysaml2",
            "binary_version": "3.0.0-3ubuntu1.16.04.4+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "python-pysaml2",
        "purl": "pkg:deb/ubuntu/python-pysaml2@3.0.0-3ubuntu1.16.04.4+esm1?arch=source\u0026distro=esm-infra/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.0.0-3ubuntu1.16.04.4+esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.4.0-0ubuntu2",
        "3.0.0-3ubuntu1",
        "3.0.0-3ubuntu1.16.04.1",
        "3.0.0-3ubuntu1.16.04.3",
        "3.0.0-3ubuntu1.16.04.4"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "python-pysaml2",
            "binary_version": "4.0.2-0ubuntu3.2"
          },
          {
            "binary_name": "python3-pysaml2",
            "binary_version": "4.0.2-0ubuntu3.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "python-pysaml2",
        "purl": "pkg:deb/ubuntu/python-pysaml2@4.0.2-0ubuntu3.2?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.0.2-0ubuntu3.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.0.0-3ubuntu2",
        "4.0.2-0ubuntu2",
        "4.0.2-0ubuntu3",
        "4.0.2-0ubuntu3.1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "python3-pysaml2",
            "binary_version": "4.9.0-0ubuntu3.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "python-pysaml2",
        "purl": "pkg:deb/ubuntu/python-pysaml2@4.9.0-0ubuntu3.1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.9.0-0ubuntu3.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.5.0+dfsg1-0ubuntu2",
        "4.9.0-0ubuntu1",
        "4.9.0-0ubuntu2",
        "4.9.0-0ubuntu3"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "python3-pysaml2",
            "binary_version": "6.1.0-0ubuntu2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "python-pysaml2",
        "purl": "pkg:deb/ubuntu/python-pysaml2@6.1.0-0ubuntu2?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.1.0-0ubuntu2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": []
    }
  ],
  "aliases": [],
  "details": "PySAML2 is a pure python implementation of SAML Version 2 Standard. PySAML2 before 6.5.0 has an improper verification of cryptographic signature vulnerability. Users of pysaml2 that use the default CryptoBackendXmlSec1 backend and need to verify signed SAML documents are impacted. PySAML2 does not ensure that a signed SAML document is correctly signed. The default CryptoBackendXmlSec1 backend is using the xmlsec1 binary to verify the signature of signed SAML documents, but by default xmlsec1 accepts any type of key found within the given document. xmlsec1 needs to be configured explicitly to only use only _x509 certificates_ for the verification process of the SAML document signature. This is fixed in PySAML2 6.5.0.",
  "id": "UBUNTU-CVE-2021-21239",
  "modified": "2025-09-08T16:46:57Z",
  "published": "2021-01-21T15:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-21239"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/IdentityPython/pysaml2/security/advisories/GHSA-5p3x-r448-pc62"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/IdentityPython/pysaml2/releases/tag/v6.5.0"
    },
    {
      "type": "REPORT",
      "url": "https://pypi.org/project/pysaml2"
    },
    {
      "type": "REPORT",
      "url": "https://www.aleksey.com/pipermail/xmlsec/2013/009717.html"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-5066-1"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-5066-2"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2021-21239"
    }
  ],
  "related": [
    "USN-5066-1",
    "USN-5066-2"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2021-21239"
  ]
}

CVE-2021-21239 (GCVE-0-2021-21239)

Vulnerability from cvelistv5 – Published: 2021-01-21 14:15 – Updated: 2024-08-03 18:09

Title

Open default xmlsec1 key-type preference

Summary

PySAML2 is a pure python implementation of SAML Version 2 Standard. PySAML2 before 6.5.0 has an improper verification of cryptographic signature vulnerability. Users of pysaml2 that use the default CryptoBackendXmlSec1 backend and need to verify signed SAML documents are impacted. PySAML2 does not ensure that a signed SAML document is correctly signed. The default CryptoBackendXmlSec1 backend is using the xmlsec1 binary to verify the signature of signed SAML documents, but by default xmlsec1 accepts any type of key found within the given document. xmlsec1 needs to be configured explicitly to only use only _x509 certificates_ for the verification process of the SAML document signature. This is fixed in PySAML2 6.5.0.

Severity

6.5 (Medium)


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

CWE

CWE-347 - Improper Verification of Cryptographic Signature

Assigner

GitHub_M mitre root

References

6 references

URL	Tags
https://github.com/IdentityPython/pysaml2/securit…	x_refsource_CONFIRM
https://pypi.org/project/pysaml2	x_refsource_MISC
https://www.aleksey.com/pipermail/xmlsec/2013/009…	x_refsource_MISC
https://github.com/IdentityPython/pysaml2/release…	x_refsource_MISC
https://github.com/IdentityPython/pysaml2/commit/…	x_refsource_MISC
https://lists.debian.org/debian-lts-announce/2021…	mailing-listx_refsource_MLIST

Impacted products

1 product

Vendor	Product	Version
IdentityPython	pysaml2	Affected: < 6.5.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-03T18:09:14.896Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_refsource_CONFIRM",
              "x_transferred"
            ],
            "url": "https://github.com/IdentityPython/pysaml2/security/advisories/GHSA-5p3x-r448-pc62"
          },
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://pypi.org/project/pysaml2"
          },
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://www.aleksey.com/pipermail/xmlsec/2013/009717.html"
          },
          {
            "tags": [
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          },
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              "x_transferred"
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          },
          {
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            "tags": [
              "mailing-list",
              "x_refsource_MLIST",
              "x_transferred"
            ],
            "url": "https://lists.debian.org/debian-lts-announce/2021/02/msg00038.html"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "pysaml2",
          "vendor": "IdentityPython",
          "versions": [
            {
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              "version": "\u003c 6.5.0"
            }
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        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "PySAML2 is a pure python implementation of SAML Version 2 Standard. PySAML2 before 6.5.0 has an improper verification of cryptographic signature vulnerability. Users of pysaml2 that use the default CryptoBackendXmlSec1 backend and need to verify signed SAML documents are impacted. PySAML2 does not ensure that a signed SAML document is correctly signed. The default CryptoBackendXmlSec1 backend is using the xmlsec1 binary to verify the signature of signed SAML documents, but by default xmlsec1 accepts any type of key found within the given document. xmlsec1 needs to be configured explicitly to only use only _x509 certificates_ for the verification process of the SAML document signature. This is fixed in PySAML2 6.5.0."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
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        "shortName": "GitHub_M"
      },
      "references": [
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          "url": "https://www.aleksey.com/pipermail/xmlsec/2013/009717.html"
        },
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          "url": "https://github.com/IdentityPython/pysaml2/releases/tag/v6.5.0"
        },
        {
          "tags": [
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          "url": "https://github.com/IdentityPython/pysaml2/commit/46578df0695269a16f1c94171f1429873f90ed99"
        },
        {
          "name": "[debian-lts-announce] 20210226 [SECURITY] [DLA 2577-1] python-pysaml2 security update",
          "tags": [
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            "x_refsource_MLIST"
          ],
          "url": "https://lists.debian.org/debian-lts-announce/2021/02/msg00038.html"
        }
      ],
      "source": {
        "advisory": "GHSA-5p3x-r448-pc62",
        "discovery": "UNKNOWN"
      },
      "title": "Open default xmlsec1 key-type preference",
      "x_legacyV4Record": {
        "CVE_data_meta": {
          "ASSIGNER": "security-advisories@github.com",
          "ID": "CVE-2021-21239",
          "STATE": "PUBLIC",
          "TITLE": "Open default xmlsec1 key-type preference"
        },
        "affects": {
          "vendor": {
            "vendor_data": [
              {
                "product": {
                  "product_data": [
                    {
                      "product_name": "pysaml2",
                      "version": {
                        "version_data": [
                          {
                            "version_value": "\u003c 6.5.0"
                          }
                        ]
                      }
                    }
                  ]
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                "vendor_name": "IdentityPython"
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        "description": {
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            }
          ]
        },
        "impact": {
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            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
            "version": "3.1"
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        "problemtype": {
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              "description": [
                {
                  "lang": "eng",
                  "value": "CWE-347 Improper Verification of Cryptographic Signature"
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          ]
        },
        "references": {
          "reference_data": [
            {
              "name": "https://github.com/IdentityPython/pysaml2/security/advisories/GHSA-5p3x-r448-pc62",
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            },
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            },
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              "refsource": "MISC",
              "url": "https://www.aleksey.com/pipermail/xmlsec/2013/009717.html"
            },
            {
              "name": "https://github.com/IdentityPython/pysaml2/releases/tag/v6.5.0",
              "refsource": "MISC",
              "url": "https://github.com/IdentityPython/pysaml2/releases/tag/v6.5.0"
            },
            {
              "name": "https://github.com/IdentityPython/pysaml2/commit/46578df0695269a16f1c94171f1429873f90ed99",
              "refsource": "MISC",
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            },
            {
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              "refsource": "MLIST",
              "url": "https://lists.debian.org/debian-lts-announce/2021/02/msg00038.html"
            }
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        },
        "source": {
          "advisory": "GHSA-5p3x-r448-pc62",
          "discovery": "UNKNOWN"
        }
      }
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  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2021-21239",
    "datePublished": "2021-01-21T14:15:21.000Z",
    "dateReserved": "2020-12-22T00:00:00.000Z",
    "dateUpdated": "2024-08-03T18:09:14.896Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}

usn-5066-1

Vulnerability from osv_ubuntu

Published

2021-09-08 11:28

Modified

2026-02-10 04:42

Summary

python-pysaml2 vulnerability

Details

Brian Wolff discovered that PySAML2 incorrectly validated cryptographic signatures. A remote attacker could possibly use this issue to alter SAML documents.

References

URL

Type

	https://ubuntu.com/security/notices/USN-5066-1	ADVISORY
	https://ubuntu.com/security/CVE-2021-21239	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2021-21239",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:18.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "python-pysaml2",
            "binary_version": "4.0.2-0ubuntu3.2"
          },
          {
            "binary_name": "python3-pysaml2",
            "binary_version": "4.0.2-0ubuntu3.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "python-pysaml2",
        "purl": "pkg:deb/ubuntu/python-pysaml2@4.0.2-0ubuntu3.2?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.0.2-0ubuntu3.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.0.0-3ubuntu2",
        "4.0.2-0ubuntu2",
        "4.0.2-0ubuntu3",
        "4.0.2-0ubuntu3.1"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2021-21239",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:20.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "python3-pysaml2",
            "binary_version": "4.9.0-0ubuntu3.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "python-pysaml2",
        "purl": "pkg:deb/ubuntu/python-pysaml2@4.9.0-0ubuntu3.1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.9.0-0ubuntu3.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.5.0+dfsg1-0ubuntu2",
        "4.9.0-0ubuntu1",
        "4.9.0-0ubuntu2",
        "4.9.0-0ubuntu3"
      ]
    }
  ],
  "aliases": [],
  "details": "Brian Wolff discovered that PySAML2 incorrectly validated cryptographic\nsignatures. A remote attacker could possibly use this issue to alter SAML\ndocuments.\n",
  "id": "USN-5066-1",
  "modified": "2026-02-10T04:42:18Z",
  "published": "2021-09-08T11:28:31Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-5066-1"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-21239"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "python-pysaml2 vulnerability",
  "upstream": [
    "UBUNTU-CVE-2021-21239"
  ]
}

usn-5066-2

Vulnerability from osv_ubuntu

Published

2021-09-08 13:28

Modified

2026-06-25 10:46

Summary

python-pysaml2 vulnerability

Details

USN-5066-1 fixed a vulnerability in PySAML2. This update provides the corresponding update for Ubuntu 16.04 ESM.

Original advisory details:

Brian Wolff discovered that PySAML2 incorrectly validated cryptographic signatures. A remote attacker could possibly use this issue to alter SAML documents.

References

URL

Type

	https://ubuntu.com/security/notices/USN-5066-2	ADVISORY
	https://ubuntu.com/security/CVE-2021-21239	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2021-21239",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:Pro:16.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "python-pysaml2",
            "binary_version": "3.0.0-3ubuntu1.16.04.4+esm1"
          },
          {
            "binary_name": "python3-pysaml2",
            "binary_version": "3.0.0-3ubuntu1.16.04.4+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "python-pysaml2",
        "purl": "pkg:deb/ubuntu/python-pysaml2@3.0.0-3ubuntu1.16.04.4+esm1?arch=source\u0026distro=esm-infra/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.0.0-3ubuntu1.16.04.4+esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.4.0-0ubuntu2",
        "3.0.0-3ubuntu1",
        "3.0.0-3ubuntu1.16.04.1",
        "3.0.0-3ubuntu1.16.04.3",
        "3.0.0-3ubuntu1.16.04.4"
      ]
    }
  ],
  "aliases": [],
  "details": "USN-5066-1 fixed a vulnerability in PySAML2. This update provides\nthe corresponding update for Ubuntu 16.04 ESM.\n\nOriginal advisory details:\n\n Brian Wolff discovered that PySAML2 incorrectly validated cryptographic\n signatures. A remote attacker could possibly use this issue to alter SAML\n documents.\n",
  "id": "USN-5066-2",
  "modified": "2026-06-25T10:46:01Z",
  "published": "2021-09-08T13:28:00Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-5066-2"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-21239"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "python-pysaml2 vulnerability",
  "upstream": [
    "UBUNTU-CVE-2021-21239"
  ]
}

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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.

Action not permitted

ubuntu-cve-2021-21239

Vulnerability from osv_ubuntu

CVE-2021-21239 (GCVE-0-2021-21239)

usn-5066-1

Vulnerability from osv_ubuntu

usn-5066-2

Vulnerability from osv_ubuntu

Tags

Sightings

Nomenclature

Related by attack behaviour