CWE-295
AllowedImproper Certificate Validation
Abstraction: Base · Status: Draft
The product does not validate, or incorrectly validates, a certificate.
2267 vulnerabilities reference this CWE, most recent first.
GHSA-F4CQ-MFH7-4385
Vulnerability from github – Published: 2026-09-30 09:31 – Updated: 2026-09-30 12:35Improper Verification of Cryptographic Signature and Improper Certificate Validation in the OPC UA driver of Apache PLC4X (PLC4J) allows an attacker in a network position between client and server to impersonate the OPC UA server and to read, forge or modify secure-channel traffic, including user credential ssent by the client.
The defect manifests differently depending on the version: - In 0.9.0 through 0.11.0 a failed message-signature check is only logged and never enforced, and there is no mechanism to verify the server certificate: it is taken from the unauthenticated GetEndpoints discovery response and used to encrypt the user's password. - In 0.12.0 through 0.13.1 the signature check is inverted (valid signatures are rejected, invalid ones accepted), and server certificates are accepted without a trust anchor by default. - In all affected versions the default security policy is None. Starting with 0.12.0 the driver additionally continues silently at a weaker security policy than the one configured, and starting with 0.13.0 endpoint selection prefers the weakest matching endpoint.
Users checking only for one of these mechanisms may wrongly conclude they are unaffected.
This issue affects Apache PLC4X: from 0.9.0 before 1.0.0.
Users are recommended to upgrade to version 1.0.0, which fixes the issue. Version 1.0.0 verifies message signatures correctly, refuses to connect unless the server certificate can be verified against a configured trust store or pinned certificate, defaults to Basic256Sha256 with SignAndEncrypt, and fails the connection if the negotiated security policy is weaker than the configured one.
{
"affected": [],
"aliases": [
"CVE-2026-102508"
],
"database_specific": {
"cwe_ids": [
"CWE-295"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-09-30T08:16:31Z",
"severity": "CRITICAL"
},
"details": "Improper Verification of Cryptographic Signature and Improper Certificate Validation in the OPC UA driver of Apache PLC4X (PLC4J) allows an attacker in a network position between client and server to impersonate the OPC UA server and to read, forge or modify secure-channel traffic, including user credential ssent by the client.\n\nThe defect manifests differently depending on the version:\n- In 0.9.0 through 0.11.0 a failed message-signature check is only logged and never enforced, and there is no mechanism to verify the server certificate: it is taken from the unauthenticated GetEndpoints discovery response and used to encrypt the user\u0027s password.\n- In 0.12.0 through 0.13.1 the signature check is inverted (valid signatures are rejected, invalid ones accepted), and server certificates are accepted without a trust anchor by default.\n- In all affected versions the default security policy is None. Starting with 0.12.0 the driver additionally continues silently at a weaker security policy than the one configured, and starting with 0.13.0 endpoint selection prefers the weakest matching endpoint.\n\nUsers checking only for one of these mechanisms may wrongly conclude they are unaffected.\n\nThis issue affects Apache PLC4X: from 0.9.0 before 1.0.0.\n\nUsers are recommended to upgrade to version 1.0.0, which fixes the issue. Version 1.0.0 verifies message signatures correctly, refuses to connect unless the server certificate can be verified against a configured trust store or pinned certificate, defaults to Basic256Sha256 with SignAndEncrypt, and fails the\nconnection if the negotiated security policy is weaker than the configured one.",
"id": "GHSA-f4cq-mfh7-4385",
"modified": "2026-09-30T12:35:14Z",
"published": "2026-09-30T09:31:09Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-102508"
},
{
"type": "WEB",
"url": "https://lists.apache.org/thread.html/o076mcnsx6wnqpdy780m7s6hddbbnjfw"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2026/09/30/4"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/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:X",
"type": "CVSS_V4"
}
]
}
GHSA-F56R-HFV8-Q98C
Vulnerability from github – Published: 2023-07-17 18:31 – Updated: 2024-04-04 06:11Mattermost iOS app fails to properly validate the server certificate while initializing the TLS connection allowing a network attacker to intercept the WebSockets connection.
{
"affected": [],
"aliases": [
"CVE-2023-3615"
],
"database_specific": {
"cwe_ids": [
"CWE-295"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-07-17T16:15:11Z",
"severity": "HIGH"
},
"details": "Mattermost iOS app fails\u00a0to properly\u00a0validate the server certificate while initializing the TLS connection allowing a network attacker to intercept the WebSockets connection.\n\n",
"id": "GHSA-f56r-hfv8-q98c",
"modified": "2024-04-04T06:11:12Z",
"published": "2023-07-17T18:31:28Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-3615"
},
{
"type": "WEB",
"url": "https://mattermost.com/security-updates"
}
],
"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-F58W-649R-QJR9
Vulnerability from github – Published: 2019-03-25 16:18 – Updated: 2024-10-27 15:34Splunk-SDK-Python before 1.6.6 does not properly verify untrusted TLS server certificates, which could result in man-in-the-middle attacks.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "splunk-sdk"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.6.6"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2019-5729"
],
"database_specific": {
"cwe_ids": [
"CWE-295"
],
"github_reviewed": true,
"github_reviewed_at": "2020-06-16T21:33:41Z",
"nvd_published_at": null,
"severity": "CRITICAL"
},
"details": "Splunk-SDK-Python before 1.6.6 does not properly verify untrusted TLS server certificates, which could result in man-in-the-middle attacks.",
"id": "GHSA-f58w-649r-qjr9",
"modified": "2024-10-27T15:34:51Z",
"published": "2019-03-25T16:18:04Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-5729"
},
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-f58w-649r-qjr9"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/splunk-sdk/PYSEC-2019-203.yaml"
},
{
"type": "PACKAGE",
"url": "https://github.com/splunk/splunk-sdk-python"
},
{
"type": "WEB",
"url": "https://www.splunk.com/view/SP-CAAAQAD"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "splunk-sdk does not properly verify untrusted TLS server certificates"
}
GHSA-F5H9-5Q52-QRX7
Vulnerability from github – Published: 2026-04-09 21:31 – Updated: 2026-04-16 21:31Missing hash/digest size and OID checks allow digests smaller than allowed when verifying ECDSA certificates, or smaller than is appropriate for the relevant key type, to be accepted by signature verification functions. This could lead to reduced security of ECDSA certificate-based authentication if the public CA key used is also known. This affects ECDSA/ECC verification when EdDSA or ML-DSA is also enabled.
{
"affected": [],
"aliases": [
"CVE-2026-5194"
],
"database_specific": {
"cwe_ids": [
"CWE-295"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-04-09T20:16:28Z",
"severity": "CRITICAL"
},
"details": "Missing hash/digest size and OID checks allow digests smaller than allowed when verifying ECDSA certificates, or smaller than is appropriate for the relevant key type, to be accepted by signature verification functions. This could lead to reduced security of ECDSA certificate-based authentication if the public CA key used is also known. This affects ECDSA/ECC verification when EdDSA or ML-DSA is also enabled.",
"id": "GHSA-f5h9-5q52-qrx7",
"modified": "2026-04-16T21:31:11Z",
"published": "2026-04-09T21:31:30Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-5194"
},
{
"type": "WEB",
"url": "https://github.com/wolfSSL/wolfssl/pull/10131"
}
],
"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"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:H/SI:L/SA:L/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:Red",
"type": "CVSS_V4"
}
]
}
GHSA-F5Q5-79FF-JH27
Vulnerability from github – Published: 2023-10-13 18:30 – Updated: 2024-04-04 08:38A potential security vulnerability has been identified in the HP ThinUpdate utility (also known as HP Recovery Image and Software Download Tool) which may lead to information disclosure. HP is releasing mitigation for the potential vulnerability.
{
"affected": [],
"aliases": [
"CVE-2023-4499"
],
"database_specific": {
"cwe_ids": [
"CWE-295"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-10-13T17:15:09Z",
"severity": "HIGH"
},
"details": "A potential security vulnerability has been identified in the HP ThinUpdate utility (also known as HP Recovery Image and Software Download Tool) which may lead to information disclosure. HP is releasing mitigation for the potential vulnerability.",
"id": "GHSA-f5q5-79ff-jh27",
"modified": "2024-04-04T08:38:17Z",
"published": "2023-10-13T18:30:20Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-4499"
},
{
"type": "WEB",
"url": "https://support.hp.com/us-en/document/ish_9440593-9440618-16"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-F6RC-73VX-29H5
Vulnerability from github – Published: 2024-07-31 21:32 – Updated: 2024-08-15 15:30An issue was discovered in filestash v0.4. The usage of the ssh.InsecureIgnoreHostKey() disables host key verification, possibly allowing attackers to obtain sensitive information via a man-in-the-middle attack.
{
"affected": [],
"aliases": [
"CVE-2024-41258"
],
"database_specific": {
"cwe_ids": [
"CWE-295",
"CWE-347"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-07-31T21:15:18Z",
"severity": "MODERATE"
},
"details": "An issue was discovered in filestash v0.4. The usage of the ssh.InsecureIgnoreHostKey() disables host key verification, possibly allowing attackers to obtain sensitive information via a man-in-the-middle attack.",
"id": "GHSA-f6rc-73vx-29h5",
"modified": "2024-08-15T15:30:53Z",
"published": "2024-07-31T21:32:38Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-41258"
},
{
"type": "WEB",
"url": "https://gist.github.com/nyxfqq/ed8c2ba3398c9e28cd8dbf0902bd8edf"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-F727-J88G-P3M8
Vulnerability from github – Published: 2022-05-13 01:38 – Updated: 2022-05-13 01:38A flaw was found in all Openshift Enterprise versions using the openshift elasticsearch plugin. An attacker with knowledge of the given name used to authenticate and access Elasticsearch can later access it without the token, bypassing authentication. This attack also requires that the Elasticsearch be configured with an external route, and the data accessed is limited to the indices.
{
"affected": [],
"aliases": [
"CVE-2017-12195"
],
"database_specific": {
"cwe_ids": [
"CWE-287",
"CWE-295"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2018-07-27T15:29:00Z",
"severity": "MODERATE"
},
"details": "A flaw was found in all Openshift Enterprise versions using the openshift elasticsearch plugin. An attacker with knowledge of the given name used to authenticate and access Elasticsearch can later access it without the token, bypassing authentication. This attack also requires that the Elasticsearch be configured with an external route, and the data accessed is limited to the indices.",
"id": "GHSA-f727-j88g-p3m8",
"modified": "2022-05-13T01:38:11Z",
"published": "2022-05-13T01:38:11Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2017-12195"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2017:3188"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2017:3389"
},
{
"type": "WEB",
"url": "https://access.redhat.com/security/cve/CVE-2017-12195"
},
{
"type": "WEB",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=1501986"
},
{
"type": "WEB",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2017-12195"
}
],
"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-F728-V2H3-3VFV
Vulnerability from github – Published: 2025-08-14 06:30 – Updated: 2025-08-14 06:30An insufficient validation on the server connection endpoint in Netskope Client allows local users to elevate privileges on the system. The insufficient validation allows Netskope Client to connect to any other server with Public Signed CA TLS certificates and send specially crafted responses to elevate privileges.
{
"affected": [],
"aliases": [
"CVE-2025-0309"
],
"database_specific": {
"cwe_ids": [
"CWE-295"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-08-14T05:15:26Z",
"severity": "MODERATE"
},
"details": "An insufficient validation on the server connection endpoint in Netskope Client allows local users to elevate privileges on the system. The insufficient validation allows Netskope Client to connect to any other server with Public Signed CA TLS certificates and send specially crafted responses to elevate privileges.",
"id": "GHSA-f728-v2h3-3vfv",
"modified": "2025-08-14T06:30:33Z",
"published": "2025-08-14T06:30:33Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-0309"
},
{
"type": "WEB",
"url": "https://blog.amberwolf.com/blog/2025/august/breaking-into-your-network-zer0-effort"
},
{
"type": "WEB",
"url": "https://www.netskope.com/company/security-compliance-and-assurance/security-advisories-and-disclosures/netskope-security-advisory-nskpsa-2025-002"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:P/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:H/SC:H/SI:H/SA:H/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-F7Q5-QG45-7VM8
Vulnerability from github – Published: 2025-07-10 09:32 – Updated: 2026-05-12 15:30A heap-buffer-overread vulnerability was found in GnuTLS in how it handles the Certificate Transparency (CT) Signed Certificate Timestamp (SCT) extension during X.509 certificate parsing. This flaw allows a malicious user to create a certificate containing a malformed SCT extension (OID 1.3.6.1.4.1.11129.2.4.2) that contains sensitive data. This issue leads to the exposure of confidential information when GnuTLS verifies certificates from certain websites when the certificate (SCT) is not checked correctly.
{
"affected": [],
"aliases": [
"CVE-2025-32989"
],
"database_specific": {
"cwe_ids": [
"CWE-295"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-07-10T08:15:24Z",
"severity": "MODERATE"
},
"details": "A heap-buffer-overread vulnerability was found in GnuTLS in how it handles the Certificate Transparency (CT) Signed Certificate Timestamp (SCT) extension during X.509 certificate parsing. This flaw allows a malicious user to create a certificate containing a malformed SCT extension (OID 1.3.6.1.4.1.11129.2.4.2) that contains sensitive data. This issue leads to the exposure of confidential information when GnuTLS verifies certificates from certain websites when the certificate (SCT) is not checked correctly.",
"id": "GHSA-f7q5-qg45-7vm8",
"modified": "2026-05-12T15:30:54Z",
"published": "2025-07-10T09:32:27Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-32989"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2025:16115"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2025:16116"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2025:17181"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2025:17348"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2025:17361"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2025:19088"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2025:22529"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:7477"
},
{
"type": "WEB",
"url": "https://access.redhat.com/security/cve/CVE-2025-32989"
},
{
"type": "WEB",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2359621"
},
{
"type": "WEB",
"url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html"
},
{
"type": "WEB",
"url": "https://lists.gnupg.org/pipermail/gnutls-help/2025-July/004883.html"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2025/07/11/3"
}
],
"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"
}
]
}
GHSA-F7VF-74CX-834M
Vulnerability from github – Published: 2022-05-24 17:32 – Updated: 2025-01-14 21:31Improper certificate validation vulnerability in OpenVPN client in Synology DiskStation Manager (DSM) before 6.2.3-25426-2 allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.
{
"affected": [],
"aliases": [
"CVE-2020-27648"
],
"database_specific": {
"cwe_ids": [
"CWE-295"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2020-10-29T09:15:00Z",
"severity": "CRITICAL"
},
"details": "Improper certificate validation vulnerability in OpenVPN client in Synology DiskStation Manager (DSM) before 6.2.3-25426-2 allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.",
"id": "GHSA-f7vf-74cx-834m",
"modified": "2025-01-14T21:31:41Z",
"published": "2022-05-24T17:32:35Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-27648"
},
{
"type": "WEB",
"url": "https://www.synology.com/security/advisory/Synology_SA_20_18"
},
{
"type": "WEB",
"url": "https://www.talosintelligence.com/vulnerability_reports/TALOS-2020-1058"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
Mitigation
Certificates should be carefully managed and checked to assure that data are encrypted with the intended owner's public key.
Mitigation
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.