Common Weakness Enumeration

CWE-295

Allowed

Improper Certificate Validation

Abstraction: Base · Status: Draft

The product does not validate, or incorrectly validates, a certificate.

1911 vulnerabilities reference this CWE, most recent first.

GHSA-4MWG-64W4-5G5M

Vulnerability from github – Published: 2023-12-21 12:30 – Updated: 2024-01-04 15:30
VLAI
Details

Improper validation of the server’s certificate chain in secure traffic scanning feature considered intermediate certificate signed using the MD5 or SHA1 algorithm as trusted.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2023-5594"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-12-21T12:15:08Z",
    "severity": "HIGH"
  },
  "details": "Improper validation of the server\u2019s certificate chain in secure traffic scanning feature considered intermediate certificate signed using the MD5 or SHA1 algorithm as trusted.",
  "id": "GHSA-4mwg-64w4-5g5m",
  "modified": "2024-01-04T15:30:21Z",
  "published": "2023-12-21T12:30:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-5594"
    },
    {
      "type": "WEB",
      "url": "https://support.eset.com/en/ca8562-eset-customer-advisory-improper-following-of-a-certificates-chain-of-trust-in-eset-security-products-fixed"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-4P6C-FXCR-RHM3

Vulnerability from github – Published: 2022-05-13 01:35 – Updated: 2022-05-13 01:35
VLAI
Details

A vulnerability in the certificate management subsystem of Cisco AnyConnect Network Access Manager and of Cisco AnyConnect Secure Mobility Client for iOS, Mac OS X, Android, Windows, and Linux could allow an unauthenticated, remote attacker to bypass the TLS certificate check when downloading certain configuration files. The vulnerability is due to improper use of Simple Certificate Enrollment Protocol and improper server certificate validation. An attacker could exploit this vulnerability by preparing malicious profile and localization files for Cisco AnyConnect to use. A successful exploit could allow the attacker to remotely change the configuration profile, a certificate, or the localization data used by AnyConnect Secure Mobility Client. Cisco Bug IDs: CSCvh23141.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2018-0334"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2018-06-07T21:29:00Z",
    "severity": "MODERATE"
  },
  "details": "A vulnerability in the certificate management subsystem of Cisco AnyConnect Network Access Manager and of Cisco AnyConnect Secure Mobility Client for iOS, Mac OS X, Android, Windows, and Linux could allow an unauthenticated, remote attacker to bypass the TLS certificate check when downloading certain configuration files. The vulnerability is due to improper use of Simple Certificate Enrollment Protocol and improper server certificate validation. An attacker could exploit this vulnerability by preparing malicious profile and localization files for Cisco AnyConnect to use. A successful exploit could allow the attacker to remotely change the configuration profile, a certificate, or the localization data used by AnyConnect Secure Mobility Client. Cisco Bug IDs: CSCvh23141.",
  "id": "GHSA-4p6c-fxcr-rhm3",
  "modified": "2022-05-13T01:35:23Z",
  "published": "2022-05-13T01:35:23Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2018-0334"
    },
    {
      "type": "WEB",
      "url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180606-AnyConnect-cert-bypass"
    },
    {
      "type": "WEB",
      "url": "http://www.securityfocus.com/bid/104430"
    },
    {
      "type": "WEB",
      "url": "http://www.securitytracker.com/id/1041075"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-4P8G-WMMC-P9F7

Vulnerability from github – Published: 2022-05-24 17:08 – Updated: 2024-03-07 21:30
VLAI
Details

Improper Certificate Validation in Node.js 10, 12, and 13 causes the process to abort when sending a crafted X.509 certificate

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2019-15604"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2020-02-07T15:15:00Z",
    "severity": "MODERATE"
  },
  "details": "Improper Certificate Validation in Node.js 10, 12, and 13 causes the process to abort when sending a crafted X.509 certificate",
  "id": "GHSA-4p8g-wmmc-p9f7",
  "modified": "2024-03-07T21:30:19Z",
  "published": "2022-05-24T17:08:13Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2019-15604"
    },
    {
      "type": "WEB",
      "url": "https://hackerone.com/reports/746733"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2020:0573"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2020:0579"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2020:0597"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2020:0598"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2020:0602"
    },
    {
      "type": "WEB",
      "url": "https://nodejs.org/en/blog/release/v10.19.0"
    },
    {
      "type": "WEB",
      "url": "https://nodejs.org/en/blog/release/v12.15.0"
    },
    {
      "type": "WEB",
      "url": "https://nodejs.org/en/blog/release/v13.8.0"
    },
    {
      "type": "WEB",
      "url": "https://nodejs.org/en/blog/vulnerability/february-2020-security-releases"
    },
    {
      "type": "WEB",
      "url": "https://security.gentoo.org/glsa/202003-48"
    },
    {
      "type": "WEB",
      "url": "https://security.netapp.com/advisory/ntap-20200221-0004"
    },
    {
      "type": "WEB",
      "url": "https://www.debian.org/security/2020/dsa-4669"
    },
    {
      "type": "WEB",
      "url": "https://www.oracle.com//security-alerts/cpujul2021.html"
    },
    {
      "type": "WEB",
      "url": "https://www.oracle.com/security-alerts/cpuapr2020.html"
    },
    {
      "type": "WEB",
      "url": "http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00008.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-4PC6-W92R-32XW

Vulnerability from github – Published: 2026-06-12 03:31 – Updated: 2026-06-23 15:32
VLAI
Details

Idira Privilege Cloud Connector versions prior 1.1.100504 under specific conditions and configuration scenarios, TLS certificate validation may not be fully enforced. CyberArk Security Bulletin: CA26-17

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-45170"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-12T02:16:42Z",
    "severity": "HIGH"
  },
  "details": "Idira Privilege Cloud Connector versions prior 1.1.100504 under specific conditions and configuration scenarios, TLS certificate validation may not be fully enforced. CyberArk Security Bulletin: CA26-17",
  "id": "GHSA-4pc6-w92r-32xw",
  "modified": "2026-06-23T15:32:30Z",
  "published": "2026-06-12T03:31:28Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-45170"
    },
    {
      "type": "WEB",
      "url": "https://docs.cyberark.com"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Amber",
      "type": "CVSS_V4"
    }
  ]
}

GHSA-4PQJ-5GG5-44JH

Vulnerability from github – Published: 2022-05-24 17:09 – Updated: 2024-04-04 02:48
VLAI
Details

An issue was discovered in openfortivpn 1.11.0 when used with OpenSSL before 1.0.2. tunnel.c mishandles certificate validation because hostname comparisons do not consider '\0' characters, as demonstrated by a good.example.com\x00evil.example.com attack.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2020-7043"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2020-02-27T18:15:00Z",
    "severity": "CRITICAL"
  },
  "details": "An issue was discovered in openfortivpn 1.11.0 when used with OpenSSL before 1.0.2. tunnel.c mishandles certificate validation because hostname comparisons do not consider \u0026#39;\\0\u0026#39; characters, as demonstrated by a good.example.com\\x00evil.example.com attack.",
  "id": "GHSA-4pqj-5gg5-44jh",
  "modified": "2024-04-04T02:48:25Z",
  "published": "2022-05-24T17:09:52Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-7043"
    },
    {
      "type": "WEB",
      "url": "https://github.com/adrienverge/openfortivpn/issues/536"
    },
    {
      "type": "WEB",
      "url": "https://github.com/adrienverge/openfortivpn/commit/6328a070ddaab16faaf008cb9a8a62439c30f2a8"
    },
    {
      "type": "WEB",
      "url": "https://github.com/adrienverge/openfortivpn/commit/cd9368c6a1b4ef91d77bb3fdbe2e5bc34aa6f4c4"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CKNKSGBVYGRRVRLFEFBEKUEJYJR5LWOF"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FF6HYIBREQGATRM5COF57MRQWKOKCWZ3"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SRVVNXCNTNMPCIAZIVR4FAGYCSU53FNA"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/CKNKSGBVYGRRVRLFEFBEKUEJYJR5LWOF"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/FF6HYIBREQGATRM5COF57MRQWKOKCWZ3"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/SRVVNXCNTNMPCIAZIVR4FAGYCSU53FNA"
    },
    {
      "type": "WEB",
      "url": "http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00009.html"
    },
    {
      "type": "WEB",
      "url": "http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00011.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-4PV6-Q257-8Q33

Vulnerability from github – Published: 2023-04-11 18:30 – Updated: 2024-04-04 03:24
VLAI
Details

An improper certificate validation vulnerability [CWE-295] in FortiAnalyzer and FortiManager 7.2.0 through 7.2.1, 7.0.0 through 7.0.5, 6.4.8 through 6.4.10 may allow a remote and unauthenticated attacker to perform a Man-in-the-Middle attack on the communication channel between the device and the remote FortiGuard server hosting outbreakalert ressources.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2023-22642"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-04-11T17:15:00Z",
    "severity": "HIGH"
  },
  "details": "An improper certificate validation vulnerability [CWE-295] in FortiAnalyzer and FortiManager 7.2.0 through 7.2.1, 7.0.0 through 7.0.5, 6.4.8 through 6.4.10 may allow a remote and unauthenticated attacker to perform a Man-in-the-Middle attack on the communication channel between the device and the remote FortiGuard server hosting outbreakalert ressources.",
  "id": "GHSA-4pv6-q257-8q33",
  "modified": "2024-04-04T03:24:40Z",
  "published": "2023-04-11T18:30:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-22642"
    },
    {
      "type": "WEB",
      "url": "https://fortiguard.com/psirt/FG-IR-22-502"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-4Q88-82VM-7283

Vulnerability from github – Published: 2026-07-06 12:31 – Updated: 2026-07-06 12:31
VLAI
Details

Improper certificate validation vulnerability in B&R Industrial Automation GmbH APROL.

This issue affects APROL: before R 4.4-01P5.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-6900"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-06T11:16:31Z",
    "severity": "CRITICAL"
  },
  "details": "Improper certificate validation vulnerability in B\u0026R Industrial Automation GmbH APROL.\n\nThis issue affects APROL: before R 4.4-01P5.",
  "id": "GHSA-4q88-82vm-7283",
  "modified": "2026-07-06T12:31:31Z",
  "published": "2026-07-06T12:31:31Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-6900"
    },
    {
      "type": "WEB",
      "url": "https://br-cws-assets.de-fra-1.linodeobjects.com/SA26P011-661853b7.pdf"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

GHSA-4QMX-9M2V-R9QW

Vulnerability from github – Published: 2022-05-24 19:15 – Updated: 2022-05-24 19:15
VLAI
Details

IBM Security Verify Bridge 1.0.5.0 could allow a user to obtain sensitive information due to improper certificate validation. IBM X-Force ID: 208155.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2021-38864"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2021-09-23T17:15:00Z",
    "severity": "HIGH"
  },
  "details": "IBM Security Verify Bridge 1.0.5.0 could allow a user to obtain sensitive information due to improper certificate validation. IBM X-Force ID: 208155.",
  "id": "GHSA-4qmx-9m2v-r9qw",
  "modified": "2022-05-24T19:15:30Z",
  "published": "2022-05-24T19:15:30Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-38864"
    },
    {
      "type": "WEB",
      "url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/208155"
    },
    {
      "type": "WEB",
      "url": "https://www.ibm.com/support/pages/node/6491651"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

GHSA-4QRJ-99R6-JFRH

Vulnerability from github – Published: 2022-05-24 17:28 – Updated: 2023-12-14 10:03
VLAI
Summary
Missing hostname validation in Email Extension Plugin
Details

Email Extension Plugin 2.75 and earlier does not perform hostname validation when connecting to the configured SMTP server. This lack of validation could be abused using a man-in-the-middle attack to intercept these connections.

Email Extension Plugin 2.76 validates the SMTP hostname when connecting via TLS by default. In Email Extension Plugin 2.75 and earlier, administrators can set the Java system property mail.smtp.ssl.checkserveridentity to true on startup to enable this protection. Alternatively, this protection can be enabled (or disabled in the new version) via the 'Advanced Email Properties' field in the plugin’s configuration in Configure System.

In case of problems, this protection can be disabled again by setting mail.smtp.ssl.checkserveridentity to false using either method.

Show details on source website

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 2.75"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.jenkins-ci.plugins:email-ext"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.76"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2020-2253"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2022-12-29T01:29:38Z",
    "nvd_published_at": "2020-09-16T14:15:00Z",
    "severity": "MODERATE"
  },
  "details": "Email Extension Plugin 2.75 and earlier does not perform hostname validation when connecting to the configured SMTP server. This lack of validation could be abused using a man-in-the-middle attack to intercept these connections.\n\nEmail Extension Plugin 2.76 validates the SMTP hostname when connecting via TLS by default. In Email Extension Plugin 2.75 and earlier, administrators can set the Java system property `mail.smtp.ssl.checkserveridentity` to `true` on startup to enable this protection. Alternatively, this protection can be enabled (or disabled in the new version) via the \u0027Advanced Email Properties\u0027 field in the plugin\u2019s configuration in Configure System.\n\nIn case of problems, this protection can be disabled again by setting `mail.smtp.ssl.checkserveridentity` to `false` using either method.",
  "id": "GHSA-4qrj-99r6-jfrh",
  "modified": "2023-12-14T10:03:59Z",
  "published": "2022-05-24T17:28:24Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-2253"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jenkinsci/email-ext-plugin/commit/ac039ba581f5946975a327709ff201b459900caa"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/jenkinsci/email-ext-plugin"
    },
    {
      "type": "WEB",
      "url": "https://www.jenkins.io/security/advisory/2020-09-16/#SECURITY-1851"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2020/09/16/3"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Missing hostname validation in Email Extension Plugin"
}

GHSA-4R5V-2F2W-H6RR

Vulnerability from github – Published: 2022-05-02 03:58 – Updated: 2022-05-02 03:58
VLAI
Details

Cerulean Studios Trillian 3.1 Basic does not check SSL certificates during MSN authentication, which allows remote attackers to obtain MSN credentials via a man-in-the-middle attack with a spoofed SSL certificate.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2009-4831"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2010-04-29T19:30:00Z",
    "severity": "MODERATE"
  },
  "details": "Cerulean Studios Trillian 3.1 Basic does not check SSL certificates during MSN authentication, which allows remote attackers to obtain MSN credentials via a man-in-the-middle attack with a spoofed SSL certificate.",
  "id": "GHSA-4r5v-2f2w-h6rr",
  "modified": "2022-05-02T03:58:42Z",
  "published": "2022-05-02T03:58:42Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2009-4831"
    },
    {
      "type": "WEB",
      "url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/51400"
    },
    {
      "type": "WEB",
      "url": "http://secunia.com/advisories/35620"
    },
    {
      "type": "WEB",
      "url": "http://www.securityfocus.com/archive/1/504573/100/0/threaded"
    },
    {
      "type": "WEB",
      "url": "http://www.securityfocus.com/bid/35509"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

Mitigation
Architecture and Design Implementation

Certificates should be carefully managed and checked to assure that data are encrypted with the intended owner's public key.

Mitigation
Implementation

If certificate pinning is being used, ensure that all relevant properties of the certificate are fully validated before the certificate is pinned, including the hostname.

CAPEC-459: Creating a Rogue Certification Authority Certificate

An adversary exploits a weakness resulting from using a hashing algorithm with weak collision resistance to generate certificate signing requests (CSR) that contain collision blocks in their "to be signed" parts. The adversary submits one CSR to be signed by a trusted certificate authority then uses the signed blob to make a second certificate appear signed by said certificate authority. Due to the hash collision, both certificates, though different, hash to the same value and so the signed blob works just as well in the second certificate. The net effect is that the adversary's second X.509 certificate, which the Certification Authority has never seen, is now signed and validated by that Certification Authority.

CAPEC-475: Signature Spoofing by Improper Validation

An adversary exploits a cryptographic weakness in the signature verification algorithm implementation to generate a valid signature without knowing the key.