Common Weakness Enumeration

CWE-295

Allowed

Improper Certificate Validation

Abstraction: Base · Status: Draft

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

1913 vulnerabilities reference this CWE, most recent first.

GHSA-GW8R-QV92-434X

Vulnerability from github – Published: 2022-05-24 17:48 – Updated: 2022-05-24 17:48
VLAI
Details

HashiCorp Vault and Vault Enterprise 1.5.1 and newer, under certain circumstances, may exclude revoked but unexpired certificates from the CRL. Fixed in 1.5.8, 1.6.4, and 1.7.1.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2021-29653"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2021-04-22T17:15:00Z",
    "severity": "HIGH"
  },
  "details": "HashiCorp Vault and Vault Enterprise 1.5.1 and newer, under certain circumstances, may exclude revoked but unexpired certificates from the CRL. Fixed in 1.5.8, 1.6.4, and 1.7.1.",
  "id": "GHSA-gw8r-qv92-434x",
  "modified": "2022-05-24T17:48:09Z",
  "published": "2022-05-24T17:48:09Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-29653"
    },
    {
      "type": "WEB",
      "url": "https://discuss.hashicorp.com/t/hcsec-2021-09-vault-s-pki-engine-crl-may-exclude-revoked-but-unexpired-certificates-after-tidy/23461/2"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

GHSA-GWF6-8H3F-PJM8

Vulnerability from github – Published: 2022-05-13 01:08 – Updated: 2025-04-20 03:37
VLAI
Details

The MoboTap Dolphin Web Browser - Fast Private Internet Search app 9.23.0 through 9.23.2 for iOS does not verify X.509 certificates from SSL servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2017-8936"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2017-05-15T18:29:00Z",
    "severity": "MODERATE"
  },
  "details": "The MoboTap Dolphin Web Browser - Fast Private Internet Search app 9.23.0 through 9.23.2 for iOS does not verify X.509 certificates from SSL servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.",
  "id": "GHSA-gwf6-8h3f-pjm8",
  "modified": "2025-04-20T03:37:44Z",
  "published": "2022-05-13T01:08:38Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2017-8936"
    },
    {
      "type": "WEB",
      "url": "https://medium.com/%40chronic_9612/follow-up-76-popular-apps-confirmed-vulnerable-to-silent-interception-of-tls-protected-data-64185035029f"
    },
    {
      "type": "WEB",
      "url": "https://medium.com/@chronic_9612/follow-up-76-popular-apps-confirmed-vulnerable-to-silent-interception-of-tls-protected-data-64185035029f"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-GWJH-7GHX-8GWW

Vulnerability from github – Published: 2023-05-19 15:30 – Updated: 2024-04-04 04:15
VLAI
Details

Cloud foundry instances having CAPI version between 1.140 and 1.152.0 along with loggregator-agent v7+ may override other users syslog drain credentials if they're aware of the client certificate used for that syslog drain. This applies even if the drain has zero certs. This would allow the user to override the private key and add or modify a certificate authority used for the connection.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2023-20881"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-05-19T15:15:08Z",
    "severity": "HIGH"
  },
  "details": "Cloud foundry instances having CAPI version between 1.140 and 1.152.0 along with loggregator-agent v7+ may override other users syslog drain credentials if they\u0027re aware of the client certificate used for that syslog drain. This applies even if the drain has zero certs. This would allow the user to override the private key and add or modify a certificate authority used for the connection.",
  "id": "GHSA-gwjh-7ghx-8gww",
  "modified": "2024-04-04T04:15:14Z",
  "published": "2023-05-19T15:30:19Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-20881"
    },
    {
      "type": "WEB",
      "url": "https://www.cloudfoundry.org/blog/cve-2023-20881-cas-for-syslog-drain-mtls-feature-can-be-overwritten"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-GX2P-6H82-CCJF

Vulnerability from github – Published: 2022-05-24 17:25 – Updated: 2022-05-24 17:25
VLAI
Details

CS2 Network P2P through 3.x, as used in millions of Internet of Things devices, suffers from an authentication flaw that allows remote attackers to perform a man-in-the-middle attack, as demonstrated by eavesdropping on user video/audio streams, capturing credentials, and compromising devices.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2020-9525"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2020-08-10T16:15:00Z",
    "severity": "MODERATE"
  },
  "details": "CS2 Network P2P through 3.x, as used in millions of Internet of Things devices, suffers from an authentication flaw that allows remote attackers to perform a man-in-the-middle attack, as demonstrated by eavesdropping on user video/audio streams, capturing credentials, and compromising devices.",
  "id": "GHSA-gx2p-6h82-ccjf",
  "modified": "2022-05-24T17:25:15Z",
  "published": "2022-05-24T17:25:15Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-9525"
    },
    {
      "type": "WEB",
      "url": "https://hacked.camera"
    },
    {
      "type": "WEB",
      "url": "https://redprocyon.com"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

GHSA-GX75-Q38P-6X2Q

Vulnerability from github – Published: 2022-05-17 02:39 – Updated: 2025-04-20 03:39
VLAI
Details

The "Charlevoix State Bank" by Charlevoix State Bank app 3.0.1 -- aka charlevoix-state-bank/id1128963717 for iOS does not verify X.509 certificates from SSL servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2017-9583"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2017-06-16T12:29:00Z",
    "severity": "MODERATE"
  },
  "details": "The \"Charlevoix State Bank\" by Charlevoix State Bank app 3.0.1 -- aka charlevoix-state-bank/id1128963717 for iOS does not verify X.509 certificates from SSL servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.",
  "id": "GHSA-gx75-q38p-6x2q",
  "modified": "2025-04-20T03:39:13Z",
  "published": "2022-05-17T02:39:39Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2017-9583"
    },
    {
      "type": "WEB",
      "url": "https://medium.com/%40chronic_9612/advisory-44-credit-union-apps-for-ios-may-allow-login-credential-exposure-4d2f380b85c5"
    },
    {
      "type": "WEB",
      "url": "https://medium.com/@chronic_9612/advisory-44-credit-union-apps-for-ios-may-allow-login-credential-exposure-4d2f380b85c5"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-GXQ5-79M2-GVVQ

Vulnerability from github – Published: 2022-12-15 21:30 – Updated: 2022-12-20 15:22
VLAI
Summary
Apache Bookkeeper vulnerable to Improper Certificate Validation
Details

The Apache Bookkeeper Java Client (before 4.14.6 and also 4.15.0) does not close the connection to the bookkeeper server when TLS hostname verification fails. This leaves the bookkeeper client vulnerable to a man in the middle attack. The problem affects BookKeeper client prior to versions 4.14.6 and 4.15.1.

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.apache.bookkeeper:bookkeeper-common"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.14.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.apache.bookkeeper:bookkeeper-common"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.15.0"
            },
            {
              "fixed": "4.15.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.15.0"
      ]
    }
  ],
  "aliases": [
    "CVE-2022-32531"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2022-12-15T23:33:41Z",
    "nvd_published_at": "2022-12-15T19:15:00Z",
    "severity": "MODERATE"
  },
  "details": "The Apache Bookkeeper Java Client (before 4.14.6 and also 4.15.0) does not close the connection to the bookkeeper server when TLS hostname verification fails. This leaves the bookkeeper client vulnerable to a man in the middle attack. The problem affects BookKeeper client prior to versions 4.14.6 and 4.15.1.",
  "id": "GHSA-gxq5-79m2-gvvq",
  "modified": "2022-12-20T15:22:58Z",
  "published": "2022-12-15T21:30:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-32531"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/apache/bookkeeper"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/apache-bookkeeper-client/PYSEC-2022-43060.yaml"
    },
    {
      "type": "WEB",
      "url": "https://lists.apache.org/thread/xyk2lfc7lzof8mksmwyympbqxts1b5s9"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Apache Bookkeeper vulnerable to Improper Certificate Validation"
}

GHSA-H289-X5WC-XCV8

Vulnerability from github – Published: 2022-02-16 22:56 – Updated: 2024-05-20 21:13
VLAI
Summary
Improper Validation of Certificate with Host Mismatch in mellium.im/xmpp/websocket
Details

Impact

If no TLS configuration is provided by the user, the websocket package constructs its own TLS configuration using recommended defaults. When looking up a WSS endpoint using the DNS TXT record method described in XEP-0156: Discovering Alternative XMPP Connection Methods the ServerName field was incorrectly being set to the name of the server returned by the TXT record request, not the name of the initial server we were attempting to connect to. This means that any attacker that can spoof a DNS record (ie. in the absence of DNSSEC, DNS-over-TLS, DNS-over-HTTPS, or similar technologies) could redirect the user to a server of their choosing and as long as it had a valid TLS certificate for itself the connection would succeed, resulting in a MITM situation.

Patches

All users should upgrade to v0.21.1.

Workarounds

To work around the issue, manually specify a TLS configuration with the correct hostname.

References

  • https://mellium.im/cve/cve-2022-24968/
  • https://nvd.nist.gov/vuln/detail/CVE-2022-24968

For more information

If you have any questions or comments about this advisory: * Reach out on XMPP to sam@samwhited.com * Email us at sam@samwhited.com

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "mellium.im/xmpp"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.18.0"
            },
            {
              "fixed": "0.21.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2022-24968"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2022-02-16T22:56:21Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "### Impact\n\nIf no TLS configuration is provided by the user, the websocket package constructs its own TLS configuration using recommended defaults. When looking up a WSS endpoint using the DNS TXT record method described in [XEP-0156: Discovering Alternative XMPP Connection Methods](https://xmpp.org/extensions/xep-0156.html) the ServerName field was incorrectly being set to the name of the server returned by the TXT record request, not the name of the initial server we were attempting to connect to. This means that any attacker that can spoof a DNS record (ie. in the absence of DNSSEC, DNS-over-TLS, DNS-over-HTTPS, or similar technologies) could redirect the user to a server of their choosing and as long as it had a valid TLS certificate for itself the connection would succeed, resulting in a MITM situation.\n\n### Patches\n\nAll users should upgrade to v0.21.1.\n\n### Workarounds\n\nTo work around the issue, manually specify a TLS configuration with the correct hostname.\n\n### References\n\n- https://mellium.im/cve/cve-2022-24968/\n- https://nvd.nist.gov/vuln/detail/CVE-2022-24968\n\n### For more information\n\nIf you have any questions or comments about this advisory:\n* Reach out on XMPP to [sam@samwhited.com](xmpp:sam@samwhited.com?msg)\n* Email us at [sam@samwhited.com](mailto:sam@samwhited.com)\n",
  "id": "GHSA-h289-x5wc-xcv8",
  "modified": "2024-05-20T21:13:34Z",
  "published": "2022-02-16T22:56:21Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/mellium/xmpp/security/advisories/GHSA-h289-x5wc-xcv8"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-24968"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mellium/xmpp/pull/260"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mellium/xmpp/commit/0d92aa486da69b71f2f4a30e62aa722c711b98ac"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/mellium/xmpp"
    },
    {
      "type": "WEB",
      "url": "https://mellium.im/cve/cve-2022-24968"
    },
    {
      "type": "WEB",
      "url": "https://mellium.im/issue/259"
    },
    {
      "type": "WEB",
      "url": "https://pkg.go.dev/vuln/GO-2022-0370"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Improper Validation of Certificate with Host Mismatch in mellium.im/xmpp/websocket"
}

GHSA-H28G-F96V-JHRG

Vulnerability from github – Published: 2022-05-24 17:24 – Updated: 2022-11-29 03:30
VLAI
Details

** DISPUTED ** An issue was discovered in RIPE NCC RPKI Validator 3.x through 3.1-2020.07.06.14.28. It allows remote attackers to bypass intended access restrictions or to cause a denial of service on dependent routing systems by strategically withholding RPKI Route Origin Authorisation ".roa" files or X509 Certificate Revocation List files from the RPKI relying party's view. NOTE: some third parties may regard this as a preferred behavior, not a vulnerability.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2020-16164"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2020-07-30T16:15:00Z",
    "severity": "HIGH"
  },
  "details": "** DISPUTED ** An issue was discovered in RIPE NCC RPKI Validator 3.x through 3.1-2020.07.06.14.28. It allows remote attackers to bypass intended access restrictions or to cause a denial of service on dependent routing systems by strategically withholding RPKI Route Origin Authorisation \".roa\" files or X509 Certificate Revocation List files from the RPKI relying party\u0027s view. NOTE: some third parties may regard this as a preferred behavior, not a vulnerability.",
  "id": "GHSA-h28g-f96v-jhrg",
  "modified": "2022-11-29T03:30:25Z",
  "published": "2022-05-24T17:24:43Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/RIPE-NCC/rpki-validator-3/security/advisories/GHSA-q76j-58cx-wp5v"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-16164"
    },
    {
      "type": "WEB",
      "url": "https://github.com/RIPE-NCC/rpki-validator-3/issues/158"
    },
    {
      "type": "WEB",
      "url": "https://github.com/RIPE-NCC/rpki-validator-3/issues/232"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-H2FW-QH29-9JV7

Vulnerability from github – Published: 2022-05-24 17:00 – Updated: 2024-03-21 03:33
VLAI
Details

systemd 239 through 243 accepts any certificate signed by a trusted certificate authority for DNS Over TLS. Server Name Indication (SNI) is not sent, and there is no hostname validation with the GnuTLS backend.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2018-21029"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2019-10-30T22:15:00Z",
    "severity": "CRITICAL"
  },
  "details": "systemd 239 through 243 accepts any certificate signed by a trusted certificate authority for DNS Over TLS. Server Name Indication (SNI) is not sent, and there is no hostname validation with the GnuTLS backend.",
  "id": "GHSA-h2fw-qh29-9jv7",
  "modified": "2024-03-21T03:33:41Z",
  "published": "2022-05-24T17:00:08Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2018-21029"
    },
    {
      "type": "WEB",
      "url": "https://github.com/systemd/systemd/issues/9397"
    },
    {
      "type": "WEB",
      "url": "https://github.com/systemd/systemd/pull/13870"
    },
    {
      "type": "WEB",
      "url": "https://blog.cloudflare.com/dns-encryption-explained"
    },
    {
      "type": "WEB",
      "url": "https://github.com/systemd/systemd/blob/v239/man/resolved.conf.xml#L199-L207"
    },
    {
      "type": "WEB",
      "url": "https://github.com/systemd/systemd/blob/v243/man/resolved.conf.xml#L196-L207"
    },
    {
      "type": "WEB",
      "url": "https://github.com/systemd/systemd/blob/v243/src/resolve/resolved-dnstls-gnutls.c#L62-L63"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4NLJVOJMB6ANDILRLDZK26YGLYBEPHKY"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/4NLJVOJMB6ANDILRLDZK26YGLYBEPHKY"
    },
    {
      "type": "WEB",
      "url": "https://security.netapp.com/advisory/ntap-20191122-0002"
    },
    {
      "type": "WEB",
      "url": "https://tools.ietf.org/html/rfc7858#section-4.1"
    }
  ],
  "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:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-H2MX-PPVP-V2RQ

Vulnerability from github – Published: 2026-02-23 18:32 – Updated: 2026-02-23 21:31
VLAI
Details

An issue pertaining to CWE-295: Improper Certificate Validation was discovered in jxcore jxm master. The application disables TLS/SSL certificate validation by setting 'rejectUnauthorized': false in HTTPS request options when 'jx_obj.IsSecure' is true

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2025-70045"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-02-23T16:29:36Z",
    "severity": "HIGH"
  },
  "details": "An issue pertaining to CWE-295: Improper Certificate Validation was discovered in jxcore jxm master. The application disables TLS/SSL certificate validation by setting \u0027rejectUnauthorized\u0027: false in HTTPS request options when \u0027jx_obj.IsSecure\u0027 is true",
  "id": "GHSA-h2mx-ppvp-v2rq",
  "modified": "2026-02-23T21:31:26Z",
  "published": "2026-02-23T18:32:02Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-70045"
    },
    {
      "type": "WEB",
      "url": "https://gist.github.com/zcxlighthouse/bd5852a409c97438016f2c476f8461d9"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jxcore"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jxcore/jxm"
    }
  ],
  "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"
    }
  ]
}

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.