CWE-287
DiscouragedImproper Authentication
Abstraction: Class · Status: Draft
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
6004 vulnerabilities reference this CWE, most recent first.
GHSA-9X4Q-26CX-FR52
Vulnerability from github – Published: 2022-05-02 03:45 – Updated: 2024-02-13 18:38login.php in Zenas PaoBacheca Guestbook 2.1, when register_globals is enabled, allows remote attackers to bypass authentication and gain administrative access by setting the login_ok parameter to 1.
{
"affected": [],
"aliases": [
"CVE-2009-3421"
],
"database_specific": {
"cwe_ids": [
"CWE-287"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2009-09-25T22:30:00Z",
"severity": "MODERATE"
},
"details": "login.php in Zenas PaoBacheca Guestbook 2.1, when register_globals is enabled, allows remote attackers to bypass authentication and gain administrative access by setting the login_ok parameter to 1.",
"id": "GHSA-9x4q-26cx-fr52",
"modified": "2024-02-13T18:38:21Z",
"published": "2022-05-02T03:45:05Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2009-3421"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/52100"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/36023"
},
{
"type": "WEB",
"url": "http://www.exploit-db.com/exploits/9293"
},
{
"type": "WEB",
"url": "http://www.osvdb.org/56757"
}
],
"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-9X66-GHQX-8G5R
Vulnerability from github – Published: 2022-05-01 18:45 – Updated: 2024-10-21 19:59FTPServer.py in pyftpdlib before 0.2.0 does not increment the attempted_logins count for a USER command that specifies an invalid username, which makes it easier for remote attackers to obtain access via a brute-force attack.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "pyftpdlib"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.2.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2007-6737"
],
"database_specific": {
"cwe_ids": [
"CWE-287"
],
"github_reviewed": true,
"github_reviewed_at": "2022-06-08T22:28:55Z",
"nvd_published_at": "2010-10-19T20:00:00Z",
"severity": "MODERATE"
},
"details": "FTPServer.py in pyftpdlib before 0.2.0 does not increment the attempted_logins count for a USER command that specifies an invalid username, which makes it easier for remote attackers to obtain access via a brute-force attack.",
"id": "GHSA-9x66-ghqx-8g5r",
"modified": "2024-10-21T19:59:03Z",
"published": "2022-05-01T18:45:57Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2007-6737"
},
{
"type": "WEB",
"url": "https://github.com/giampaolo/pyftpdlib/issues/20"
},
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-9x66-ghqx-8g5r"
},
{
"type": "PACKAGE",
"url": "https://github.com/giampaolo/pyftpdlib"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/pyftpdlib/PYSEC-2010-21.yaml"
},
{
"type": "WEB",
"url": "http://code.google.com/p/pyftpdlib/issues/detail?id=20"
},
{
"type": "WEB",
"url": "http://code.google.com/p/pyftpdlib/source/browse/trunk/HISTORY"
},
{
"type": "WEB",
"url": "http://code.google.com/p/pyftpdlib/source/detail?r=23"
},
{
"type": "WEB",
"url": "http://code.google.com/p/pyftpdlib/source/diff?spec=svn23\u0026r=23\u0026format=side\u0026path=/trunk/pyftpdlib/FTPServer.py"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Improper Authentication in pyftpdlib"
}
GHSA-9X68-6G6C-VJ48
Vulnerability from github – Published: 2022-05-24 17:17 – Updated: 2023-08-16 18:30A vulnerability in the Kerberos authentication feature of Cisco Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to impersonate the Kerberos key distribution center (KDC) and bypass authentication on an affected device that is configured to perform Kerberos authentication for VPN or local device access. The vulnerability is due to insufficient identity verification of the KDC when a successful authentication response is received. An attacker could exploit this vulnerability by spoofing the KDC server response to the ASA device. This malicious response would not have been authenticated by the KDC. A successful attack could allow an attacker to bypass Kerberos authentication.
{
"affected": [],
"aliases": [
"CVE-2020-3125"
],
"database_specific": {
"cwe_ids": [
"CWE-287"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2020-05-06T17:15:00Z",
"severity": "MODERATE"
},
"details": "A vulnerability in the Kerberos authentication feature of Cisco Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to impersonate the Kerberos key distribution center (KDC) and bypass authentication on an affected device that is configured to perform Kerberos authentication for VPN or local device access. The vulnerability is due to insufficient identity verification of the KDC when a successful authentication response is received. An attacker could exploit this vulnerability by spoofing the KDC server response to the ASA device. This malicious response would not have been authenticated by the KDC. A successful attack could allow an attacker to bypass Kerberos authentication.",
"id": "GHSA-9x68-6g6c-vj48",
"modified": "2023-08-16T18:30:18Z",
"published": "2022-05-24T17:17:16Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-3125"
},
{
"type": "WEB",
"url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-asa-kerberos-bypass-96Gghe2sS"
}
],
"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-9X6J-JM6V-984F
Vulnerability from github – Published: 2022-05-13 01:33 – Updated: 2022-05-13 01:33LCDS Laquis SCADA prior to version 4.1.0.4150 allows an authentication bypass, which may allow an attacker access to sensitive data.
{
"affected": [],
"aliases": [
"CVE-2018-19000"
],
"database_specific": {
"cwe_ids": [
"CWE-287"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2019-02-05T18:29:00Z",
"severity": "MODERATE"
},
"details": "LCDS Laquis SCADA prior to version 4.1.0.4150 allows an authentication bypass, which may allow an attacker access to sensitive data.",
"id": "GHSA-9x6j-jm6v-984f",
"modified": "2022-05-13T01:33:39Z",
"published": "2022-05-13T01:33:39Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2018-19000"
},
{
"type": "WEB",
"url": "https://ics-cert.us-cert.gov/advisories/ICSA-19-015-01"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/106634"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-9X8H-HFMC-8J5R
Vulnerability from github – Published: 2025-09-09 18:31 – Updated: 2025-10-17 18:31SMB Server might be susceptible to relay attacks depending on the configuration. An attacker who successfully exploited these vulnerabilities could perform relay attacks and make the users subject to elevation of privilege attacks. The SMB Server already supports mechanisms for hardening against relay attacks:
SMB Server signing SMB Server Extended Protection for Authentication (EPA)
Microsoft is releasing this CVE to provide customers with audit capabilities to help them to assess their environment and to identify any potential device or software incompatibility issues before deploying SMB Server hardening measures that protect against relay attacks. If you have not already enabled SMB Server hardening measures, we advise customers to take the following actions to be protected from these relay attacks:
Assess your environment by utilizing the audit capabilities that we are exposing in the September 2025 security updates. See Support for Audit Events to deploy SMB Server Hardening—SMB Server Signing & SMB Server EPA. Adopt appropriate SMB Server hardening measures.
{
"affected": [],
"aliases": [
"CVE-2025-55234"
],
"database_specific": {
"cwe_ids": [
"CWE-287"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-09-09T17:16:06Z",
"severity": "HIGH"
},
"details": "SMB Server might be susceptible to relay attacks depending on the configuration. An attacker who successfully exploited these vulnerabilities could perform relay attacks and make the users subject to elevation of privilege attacks.\nThe SMB Server already supports mechanisms for hardening against relay attacks:\n\nSMB Server signing\nSMB Server Extended Protection for Authentication (EPA)\n\nMicrosoft is releasing this CVE to provide customers with audit capabilities to help them to assess their environment and to identify any potential device or software incompatibility issues before deploying SMB Server hardening measures that protect against relay attacks.\nIf you have not already enabled SMB Server hardening measures, we advise customers to take the following actions to be protected from these relay attacks:\n\nAssess your environment by utilizing the audit capabilities that we are exposing in the September 2025 security updates. See Support for Audit Events to deploy SMB Server Hardening\u2014SMB Server Signing \u0026amp; SMB Server EPA.\nAdopt appropriate SMB Server hardening measures.",
"id": "GHSA-9x8h-hfmc-8j5r",
"modified": "2025-10-17T18:31:07Z",
"published": "2025-09-09T18:31:23Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-55234"
},
{
"type": "WEB",
"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-55234"
},
{
"type": "WEB",
"url": "https://www.vicarius.io/vsociety/posts/cve-2025-55234-detection-script-smb-server-vulnerability-affecting-microsoft-systems"
},
{
"type": "WEB",
"url": "https://www.vicarius.io/vsociety/posts/cve-2025-55234-mitigation-script-smb-server-vulnerability-affecting-microsoft-systems"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-9X8W-8G8P-2QGX
Vulnerability from github – Published: 2022-03-11 00:02 – Updated: 2022-03-17 00:01otris Update Manager 1.2.1.0 allows local users to achieve SYSTEM access via unauthenticated calls to exposed interfaces over a .NET named pipe. A remote attack may be possible as well, by leveraging WsHTTPBinding for HTTP traffic on TCP port 9000.
{
"affected": [],
"aliases": [
"CVE-2021-40376"
],
"database_specific": {
"cwe_ids": [
"CWE-287"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-03-10T17:43:00Z",
"severity": "HIGH"
},
"details": "otris Update Manager 1.2.1.0 allows local users to achieve SYSTEM access via unauthenticated calls to exposed interfaces over a .NET named pipe. A remote attack may be possible as well, by leveraging WsHTTPBinding for HTTP traffic on TCP port 9000.",
"id": "GHSA-9x8w-8g8p-2qgx",
"modified": "2022-03-17T00:01:50Z",
"published": "2022-03-11T00:02:29Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-40376"
},
{
"type": "WEB",
"url": "https://www.otris.com"
},
{
"type": "WEB",
"url": "https://www.tuv.com/content-media-files/master-content/global-landingpages/images/vulnerability-disclosure/tuv-rheinland-security-advisory-local-privilege-escalation-vulnerability-in-otris-update-manager.pdf"
},
{
"type": "WEB",
"url": "https://www.tuv.com/landingpage/en/vulnerability-disclosure"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-9XQC-M7WJ-2PVM
Vulnerability from github – Published: 2022-05-13 01:45 – Updated: 2022-05-13 01:45A vulnerability in Cisco WebEx Meetings Server could allow an authenticated, remote attacker to conduct arbitrary password changes against any non-administrative user. More Information: CSCuz03345. Known Affected Releases: 2.6. Known Fixed Releases: 2.7.1.12.
{
"affected": [],
"aliases": [
"CVE-2017-3795"
],
"database_specific": {
"cwe_ids": [
"CWE-287"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2017-01-26T07:59:00Z",
"severity": "MODERATE"
},
"details": "A vulnerability in Cisco WebEx Meetings Server could allow an authenticated, remote attacker to conduct arbitrary password changes against any non-administrative user. More Information: CSCuz03345. Known Affected Releases: 2.6. Known Fixed Releases: 2.7.1.12.",
"id": "GHSA-9xqc-m7wj-2pvm",
"modified": "2022-05-13T01:45:53Z",
"published": "2022-05-13T01:45:53Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2017-3795"
},
{
"type": "WEB",
"url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170118-wms1"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/95643"
},
{
"type": "WEB",
"url": "http://www.securitytracker.com/id/1037650"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-9XR4-5399-5V72
Vulnerability from github – Published: 2022-05-17 00:37 – Updated: 2022-05-17 00:37Xigla Software Absolute News Manager.NET 5.1 allows remote attackers to bypass authentication and gain administrative access by setting a cookie to a certain value.
{
"affected": [],
"aliases": [
"CVE-2008-6856"
],
"database_specific": {
"cwe_ids": [
"CWE-287"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2009-07-14T14:30:00Z",
"severity": "HIGH"
},
"details": "Xigla Software Absolute News Manager.NET 5.1 allows remote attackers to bypass authentication and gain administrative access by setting a cookie to a certain value.",
"id": "GHSA-9xr4-5399-5v72",
"modified": "2022-05-17T00:37:41Z",
"published": "2022-05-17T00:37:41Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2008-6856"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/46301"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/exploits/6900"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/32472"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/32024"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-9XRJ-439H-62HG
Vulnerability from github – Published: 2022-05-17 01:38 – Updated: 2022-07-12 22:16The HTTP Digest Access Authentication implementation in Apache Tomcat 5.5.x before 5.5.36, 6.x before 6.0.36, and 7.x before 7.0.30 caches information about the authenticated user within the session state, which makes it easier for remote attackers to bypass authentication via vectors related to the session ID.
{
"affected": [
{
"package": {
"ecosystem": "Maven",
"name": "org.apache.tomcat:tomcat-catalina"
},
"ranges": [
{
"events": [
{
"introduced": "5.5.0"
},
{
"fixed": "5.5.36"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Maven",
"name": "org.apache.tomcat:tomcat-catalina"
},
"ranges": [
{
"events": [
{
"introduced": "6.0.0"
},
{
"fixed": "6.0.36"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Maven",
"name": "org.apache.tomcat:tomcat-catalina"
},
"ranges": [
{
"events": [
{
"introduced": "7.0.0"
},
{
"fixed": "7.0.30"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2012-5886"
],
"database_specific": {
"cwe_ids": [
"CWE-287"
],
"github_reviewed": true,
"github_reviewed_at": "2022-07-12T22:16:12Z",
"nvd_published_at": "2012-11-17T19:55:00Z",
"severity": "MODERATE"
},
"details": "The HTTP Digest Access Authentication implementation in Apache Tomcat 5.5.x before 5.5.36, 6.x before 6.0.36, and 7.x before 7.0.30 caches information about the authenticated user within the session state, which makes it easier for remote attackers to bypass authentication via vectors related to the session ID.",
"id": "GHSA-9xrj-439h-62hg",
"modified": "2022-07-12T22:16:12Z",
"published": "2022-05-17T01:38:30Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2012-5886"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/80407"
},
{
"type": "WEB",
"url": "http://lists.opensuse.org/opensuse-updates/2012-12/msg00089.html"
},
{
"type": "WEB",
"url": "http://lists.opensuse.org/opensuse-updates/2012-12/msg00090.html"
},
{
"type": "WEB",
"url": "http://lists.opensuse.org/opensuse-updates/2013-01/msg00037.html"
},
{
"type": "WEB",
"url": "http://rhn.redhat.com/errata/RHSA-2013-0623.html"
},
{
"type": "WEB",
"url": "http://rhn.redhat.com/errata/RHSA-2013-0629.html"
},
{
"type": "WEB",
"url": "http://rhn.redhat.com/errata/RHSA-2013-0631.html"
},
{
"type": "WEB",
"url": "http://rhn.redhat.com/errata/RHSA-2013-0632.html"
},
{
"type": "WEB",
"url": "http://rhn.redhat.com/errata/RHSA-2013-0640.html"
},
{
"type": "WEB",
"url": "http://rhn.redhat.com/errata/RHSA-2013-0647.html"
},
{
"type": "WEB",
"url": "http://rhn.redhat.com/errata/RHSA-2013-0648.html"
},
{
"type": "WEB",
"url": "http://rhn.redhat.com/errata/RHSA-2013-0726.html"
},
{
"type": "WEB",
"url": "http://svn.apache.org/viewvc?view=revision\u0026revision=1377807"
},
{
"type": "WEB",
"url": "http://svn.apache.org/viewvc?view=revision\u0026revision=1380829"
},
{
"type": "WEB",
"url": "http://svn.apache.org/viewvc?view=revision\u0026revision=1392248"
},
{
"type": "WEB",
"url": "http://tomcat.apache.org/security-5.html"
},
{
"type": "WEB",
"url": "http://tomcat.apache.org/security-6.html"
},
{
"type": "WEB",
"url": "http://tomcat.apache.org/security-7.html"
},
{
"type": "WEB",
"url": "http://www-01.ibm.com/support/docview.wss?uid=swg21626891"
},
{
"type": "WEB",
"url": "http://www.ubuntu.com/usn/USN-1637-1"
}
],
"schema_version": "1.4.0",
"severity": [],
"summary": "Improper Authentication in Apache Tomcat"
}
GHSA-9XX5-CV6J-X533
Vulnerability from github – Published: 2026-04-29 21:58 – Updated: 2026-05-08 20:14Summary
The OIDC token introspection endpoint (/modules/sso/index.php/oidc/introspect) always returns {"active": true} for every request, regardless of whether a valid token is provided, whether the token is expired, revoked, or completely fabricated. The endpoint performs no authentication of the calling resource server and no validation of the submitted token. Any resource server that relies on this introspection endpoint to validate access tokens will accept all requests as authorized, enabling complete authentication bypass.
Additionally, the OIDC token revocation endpoint (/oidc/revoke) returns {"revoked": true} without actually revoking any token, preventing resource servers from invalidating compromised credentials.
Details
The vulnerability is in src/SSO/Service/OIDCService.php, lines 604-619:
public function handleIntrospectionRequest() {
// TODO_RK
if (!$this->isServiceSetup) {
$this->setupService();
}
return new JsonResponse(["active" => true]);
}
public function handleRevocationRequest() {
// TODO_RK
if (!$this->isServiceSetup) {
$this->setupService();
}
return new JsonResponse(["revoked" => true]);
}
The introspection endpoint is routed at modules/sso/index.php, line 58-59:
} elseif (strpos($requestUri, '/oidc/introspect') !== false) {
$response = $oidcService->handleIntrospectionRequest();
The router comment at line 35 says "Login checks will be done in the individual endpoint handler functions!" but neither handleIntrospectionRequest nor handleRevocationRequest perform any authentication or authorization checks.
Per RFC 7662 (OAuth 2.0 Token Introspection), the introspection endpoint:
1. MUST authenticate the calling resource server (Section 2.1)
2. MUST validate the submitted token against its database
3. MUST return {"active": false} for invalid, expired, or revoked tokens
The current implementation violates all three requirements.
Attack flow:
1. Attacker obtains a resource server's endpoint URL that uses Admidio as its OIDC provider
2. Attacker crafts any arbitrary string as a Bearer token
3. Resource server sends the fabricated token to /oidc/introspect for validation
4. Admidio returns {"active": true} without any checks
5. Resource server accepts the fabricated token as valid and grants access
The revocation bypass compounds this: If a legitimate token is stolen, the resource server or client application cannot revoke it. Calling /oidc/revoke returns success without actually revoking the token in the database, so the stolen token remains usable indefinitely (until its expiry time).
PoC
# Step 1: Confirm the introspection endpoint exists and always returns active
# No valid token needed - any string works
curl -X POST https://TARGET/modules/sso/index.php/oidc/introspect \
-d "token=COMPLETELY_FABRICATED_TOKEN_12345"
# Expected response: {"active":true}
# Step 2: Try with an empty token
curl -X POST https://TARGET/modules/sso/index.php/oidc/introspect \
-d "token="
# Expected response: {"active":true}
# Step 3: Demonstrate that revocation is also broken
curl -X POST https://TARGET/modules/sso/index.php/oidc/revoke \
-d "token=any_valid_token_here"
# Expected response: {"revoked":true}
# But the token is NOT actually revoked in the database
# Step 4: Verify the token is still active after "revocation"
curl -X POST https://TARGET/modules/sso/index.php/oidc/introspect \
-d "token=any_valid_token_here"
# Still returns: {"active":true}
Impact
- Authentication Bypass on Resource Servers: Any application (wiki, CMS, project management tool, etc.) configured to validate tokens against this Admidio OIDC introspection endpoint will accept completely fabricated tokens. An attacker can impersonate any user on all connected resource servers.
- Inability to Revoke Compromised Tokens: If a legitimate access token is leaked or stolen, there is no way to revoke it through the standard OIDC revocation flow. The token remains valid until its 1-hour expiry.
- Scope Change (S:C): The vulnerability in the Admidio authorization server directly impacts the security of all connected resource servers (different security authority), which is why the CVSS scope is Changed.
Recommended Fix
Replace the stub implementations with proper token introspection and revocation logic:
public function handleIntrospectionRequest() {
if (!$this->isServiceSetup) {
$this->setupService();
}
$request = $this->getRequest();
// 1. Authenticate the resource server (RFC 7662 Section 2.1)
// The resource server MUST authenticate using client credentials
$clientId = $request->getParsedBody()['client_id'] ?? null;
$clientSecret = $request->getParsedBody()['client_secret'] ?? null;
if (!$clientId || !$this->clientRepository->validateClient($clientId, $clientSecret, null)) {
return new JsonResponse(['error' => 'invalid_client'], 401);
}
// 2. Get and validate the token
$tokenValue = $request->getParsedBody()['token'] ?? '';
if (empty($tokenValue)) {
return new JsonResponse(['active' => false]);
}
try {
// Validate the token using the resource server
$validatedRequest = $this->resourceServer->validateAuthenticatedRequest(
$request->withHeader('Authorization', 'Bearer ' . $tokenValue)
);
$tokenId = $validatedRequest->getAttribute('oauth_access_token_id');
// Check if token is revoked
if ($this->accessTokenRepository->isAccessTokenRevoked($tokenId)) {
return new JsonResponse(['active' => false]);
}
$token = $this->accessTokenRepository->getToken($tokenId);
// Check expiry
if ($token->getExpiryDateTime() < new \DateTimeImmutable()) {
return new JsonResponse(['active' => false]);
}
return new JsonResponse([
'active' => true,
'sub' => $token->getUserIdentifier(),
'client_id' => $token->getClient()->getIdentifier(),
'exp' => $token->getExpiryDateTime()->getTimestamp(),
'scope' => implode(' ', array_map(fn($s) => $s->getIdentifier(), $token->getScopes())),
]);
} catch (\Exception $e) {
return new JsonResponse(['active' => false]);
}
}
public function handleRevocationRequest() {
if (!$this->isServiceSetup) {
$this->setupService();
}
$request = $this->getRequest();
// Authenticate the client
$clientId = $request->getParsedBody()['client_id'] ?? null;
$clientSecret = $request->getParsedBody()['client_secret'] ?? null;
if (!$clientId || !$this->clientRepository->validateClient($clientId, $clientSecret, null)) {
return new JsonResponse(['error' => 'invalid_client'], 401);
}
$tokenValue = $request->getParsedBody()['token'] ?? '';
if (!empty($tokenValue)) {
try {
$validatedRequest = $this->resourceServer->validateAuthenticatedRequest(
$request->withHeader('Authorization', 'Bearer ' . $tokenValue)
);
$tokenId = $validatedRequest->getAttribute('oauth_access_token_id');
$this->accessTokenRepository->revokeAccessToken($tokenId);
} catch (\Exception $e) {
// RFC 7009: The server responds with HTTP 200 even for invalid tokens
}
}
return new JsonResponse([], 200);
}
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 5.0.8"
},
"package": {
"ecosystem": "Packagist",
"name": "admidio/admidio"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "5.0.9"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-41671"
],
"database_specific": {
"cwe_ids": [
"CWE-287"
],
"github_reviewed": true,
"github_reviewed_at": "2026-04-29T21:58:56Z",
"nvd_published_at": "2026-05-07T04:16:32Z",
"severity": "MODERATE"
},
"details": "## Summary\n\nThe OIDC token introspection endpoint (`/modules/sso/index.php/oidc/introspect`) always returns `{\"active\": true}` for every request, regardless of whether a valid token is provided, whether the token is expired, revoked, or completely fabricated. The endpoint performs no authentication of the calling resource server and no validation of the submitted token. Any resource server that relies on this introspection endpoint to validate access tokens will accept all requests as authorized, enabling complete authentication bypass.\n\nAdditionally, the OIDC token revocation endpoint (`/oidc/revoke`) returns `{\"revoked\": true}` without actually revoking any token, preventing resource servers from invalidating compromised credentials.\n\n## Details\n\nThe vulnerability is in `src/SSO/Service/OIDCService.php`, lines 604-619:\n\n```php\npublic function handleIntrospectionRequest() {\n // TODO_RK\n if (!$this-\u003eisServiceSetup) {\n $this-\u003esetupService();\n }\n return new JsonResponse([\"active\" =\u003e true]);\n}\n\npublic function handleRevocationRequest() {\n // TODO_RK\n if (!$this-\u003eisServiceSetup) {\n $this-\u003esetupService();\n }\n\n return new JsonResponse([\"revoked\" =\u003e true]);\n}\n```\n\nThe introspection endpoint is routed at `modules/sso/index.php`, line 58-59:\n\n```php\n} elseif (strpos($requestUri, \u0027/oidc/introspect\u0027) !== false) {\n $response = $oidcService-\u003ehandleIntrospectionRequest();\n```\n\nThe router comment at line 35 says \"Login checks will be done in the individual endpoint handler functions!\" but neither `handleIntrospectionRequest` nor `handleRevocationRequest` perform any authentication or authorization checks.\n\nPer RFC 7662 (OAuth 2.0 Token Introspection), the introspection endpoint:\n1. MUST authenticate the calling resource server (Section 2.1)\n2. MUST validate the submitted token against its database\n3. MUST return `{\"active\": false}` for invalid, expired, or revoked tokens\n\nThe current implementation violates all three requirements.\n\n**Attack flow:**\n1. Attacker obtains a resource server\u0027s endpoint URL that uses Admidio as its OIDC provider\n2. Attacker crafts any arbitrary string as a Bearer token\n3. Resource server sends the fabricated token to `/oidc/introspect` for validation\n4. Admidio returns `{\"active\": true}` without any checks\n5. Resource server accepts the fabricated token as valid and grants access\n\n**The revocation bypass compounds this:** If a legitimate token is stolen, the resource server or client application cannot revoke it. Calling `/oidc/revoke` returns success without actually revoking the token in the database, so the stolen token remains usable indefinitely (until its expiry time).\n\n## PoC\n\n```bash\n# Step 1: Confirm the introspection endpoint exists and always returns active\n# No valid token needed - any string works\ncurl -X POST https://TARGET/modules/sso/index.php/oidc/introspect \\\n -d \"token=COMPLETELY_FABRICATED_TOKEN_12345\"\n\n# Expected response: {\"active\":true}\n\n# Step 2: Try with an empty token\ncurl -X POST https://TARGET/modules/sso/index.php/oidc/introspect \\\n -d \"token=\"\n\n# Expected response: {\"active\":true}\n\n# Step 3: Demonstrate that revocation is also broken\ncurl -X POST https://TARGET/modules/sso/index.php/oidc/revoke \\\n -d \"token=any_valid_token_here\"\n\n# Expected response: {\"revoked\":true}\n# But the token is NOT actually revoked in the database\n\n# Step 4: Verify the token is still active after \"revocation\"\ncurl -X POST https://TARGET/modules/sso/index.php/oidc/introspect \\\n -d \"token=any_valid_token_here\"\n\n# Still returns: {\"active\":true}\n```\n\n## Impact\n\n- **Authentication Bypass on Resource Servers**: Any application (wiki, CMS, project management tool, etc.) configured to validate tokens against this Admidio OIDC introspection endpoint will accept completely fabricated tokens. An attacker can impersonate any user on all connected resource servers.\n- **Inability to Revoke Compromised Tokens**: If a legitimate access token is leaked or stolen, there is no way to revoke it through the standard OIDC revocation flow. The token remains valid until its 1-hour expiry.\n- **Scope Change (S:C)**: The vulnerability in the Admidio authorization server directly impacts the security of all connected resource servers (different security authority), which is why the CVSS scope is Changed.\n\n## Recommended Fix\n\nReplace the stub implementations with proper token introspection and revocation logic:\n\n```php\npublic function handleIntrospectionRequest() {\n if (!$this-\u003eisServiceSetup) {\n $this-\u003esetupService();\n }\n \n $request = $this-\u003egetRequest();\n \n // 1. Authenticate the resource server (RFC 7662 Section 2.1)\n // The resource server MUST authenticate using client credentials\n $clientId = $request-\u003egetParsedBody()[\u0027client_id\u0027] ?? null;\n $clientSecret = $request-\u003egetParsedBody()[\u0027client_secret\u0027] ?? null;\n \n if (!$clientId || !$this-\u003eclientRepository-\u003evalidateClient($clientId, $clientSecret, null)) {\n return new JsonResponse([\u0027error\u0027 =\u003e \u0027invalid_client\u0027], 401);\n }\n \n // 2. Get and validate the token\n $tokenValue = $request-\u003egetParsedBody()[\u0027token\u0027] ?? \u0027\u0027;\n if (empty($tokenValue)) {\n return new JsonResponse([\u0027active\u0027 =\u003e false]);\n }\n \n try {\n // Validate the token using the resource server\n $validatedRequest = $this-\u003eresourceServer-\u003evalidateAuthenticatedRequest(\n $request-\u003ewithHeader(\u0027Authorization\u0027, \u0027Bearer \u0027 . $tokenValue)\n );\n \n $tokenId = $validatedRequest-\u003egetAttribute(\u0027oauth_access_token_id\u0027);\n \n // Check if token is revoked\n if ($this-\u003eaccessTokenRepository-\u003eisAccessTokenRevoked($tokenId)) {\n return new JsonResponse([\u0027active\u0027 =\u003e false]);\n }\n \n $token = $this-\u003eaccessTokenRepository-\u003egetToken($tokenId);\n \n // Check expiry\n if ($token-\u003egetExpiryDateTime() \u003c new \\DateTimeImmutable()) {\n return new JsonResponse([\u0027active\u0027 =\u003e false]);\n }\n \n return new JsonResponse([\n \u0027active\u0027 =\u003e true,\n \u0027sub\u0027 =\u003e $token-\u003egetUserIdentifier(),\n \u0027client_id\u0027 =\u003e $token-\u003egetClient()-\u003egetIdentifier(),\n \u0027exp\u0027 =\u003e $token-\u003egetExpiryDateTime()-\u003egetTimestamp(),\n \u0027scope\u0027 =\u003e implode(\u0027 \u0027, array_map(fn($s) =\u003e $s-\u003egetIdentifier(), $token-\u003egetScopes())),\n ]);\n } catch (\\Exception $e) {\n return new JsonResponse([\u0027active\u0027 =\u003e false]);\n }\n}\n\npublic function handleRevocationRequest() {\n if (!$this-\u003eisServiceSetup) {\n $this-\u003esetupService();\n }\n \n $request = $this-\u003egetRequest();\n \n // Authenticate the client\n $clientId = $request-\u003egetParsedBody()[\u0027client_id\u0027] ?? null;\n $clientSecret = $request-\u003egetParsedBody()[\u0027client_secret\u0027] ?? null;\n \n if (!$clientId || !$this-\u003eclientRepository-\u003evalidateClient($clientId, $clientSecret, null)) {\n return new JsonResponse([\u0027error\u0027 =\u003e \u0027invalid_client\u0027], 401);\n }\n \n $tokenValue = $request-\u003egetParsedBody()[\u0027token\u0027] ?? \u0027\u0027;\n if (!empty($tokenValue)) {\n try {\n $validatedRequest = $this-\u003eresourceServer-\u003evalidateAuthenticatedRequest(\n $request-\u003ewithHeader(\u0027Authorization\u0027, \u0027Bearer \u0027 . $tokenValue)\n );\n $tokenId = $validatedRequest-\u003egetAttribute(\u0027oauth_access_token_id\u0027);\n $this-\u003eaccessTokenRepository-\u003erevokeAccessToken($tokenId);\n } catch (\\Exception $e) {\n // RFC 7009: The server responds with HTTP 200 even for invalid tokens\n }\n }\n \n return new JsonResponse([], 200);\n}\n```",
"id": "GHSA-9xx5-cv6j-x533",
"modified": "2026-05-08T20:14:32Z",
"published": "2026-04-29T21:58:56Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/Admidio/admidio/security/advisories/GHSA-9xx5-cv6j-x533"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-41671"
},
{
"type": "PACKAGE",
"url": "https://github.com/Admidio/admidio"
},
{
"type": "WEB",
"url": "https://github.com/Admidio/admidio/releases/tag/v5.0.9"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N",
"type": "CVSS_V3"
}
],
"summary": "Admidio: OIDC Token Introspection Endpoint Returns Active for All Tokens Without Validation"
}
Mitigation
Strategy: Libraries or Frameworks
Use an authentication framework or library such as the OWASP ESAPI Authentication feature.
CAPEC-114: Authentication Abuse
An attacker obtains unauthorized access to an application, service or device either through knowledge of the inherent weaknesses of an authentication mechanism, or by exploiting a flaw in the authentication scheme's implementation. In such an attack an authentication mechanism is functioning but a carefully controlled sequence of events causes the mechanism to grant access to the attacker.
CAPEC-115: Authentication Bypass
An attacker gains access to application, service, or device with the privileges of an authorized or privileged user by evading or circumventing an authentication mechanism. The attacker is therefore able to access protected data without authentication ever having taken place.
CAPEC-151: Identity Spoofing
Identity Spoofing refers to the action of assuming (i.e., taking on) the identity of some other entity (human or non-human) and then using that identity to accomplish a goal. An adversary may craft messages that appear to come from a different principle or use stolen / spoofed authentication credentials.
CAPEC-194: Fake the Source of Data
An adversary takes advantage of improper authentication to provide data or services under a falsified identity. The purpose of using the falsified identity may be to prevent traceability of the provided data or to assume the rights granted to another individual. One of the simplest forms of this attack would be the creation of an email message with a modified "From" field in order to appear that the message was sent from someone other than the actual sender. The root of the attack (in this case the email system) fails to properly authenticate the source and this results in the reader incorrectly performing the instructed action. Results of the attack vary depending on the details of the attack, but common results include privilege escalation, obfuscation of other attacks, and data corruption/manipulation.
CAPEC-22: Exploiting Trust in Client
An attack of this type exploits vulnerabilities in client/server communication channel authentication and data integrity. It leverages the implicit trust a server places in the client, or more importantly, that which the server believes is the client. An attacker executes this type of attack by communicating directly with the server where the server believes it is communicating only with a valid client. There are numerous variations of this type of attack.
CAPEC-57: Utilizing REST's Trust in the System Resource to Obtain Sensitive Data
This attack utilizes a REST(REpresentational State Transfer)-style applications' trust in the system resources and environment to obtain sensitive data once SSL is terminated.
CAPEC-593: Session Hijacking
This type of attack involves an adversary that exploits weaknesses in an application's use of sessions in performing authentication. The adversary is able to steal or manipulate an active session and use it to gain unathorized access to the application.
CAPEC-633: Token Impersonation
An adversary exploits a weakness in authentication to create an access token (or equivalent) that impersonates a different entity, and then associates a process/thread to that that impersonated token. This action causes a downstream user to make a decision or take action that is based on the assumed identity, and not the response that blocks the adversary.
CAPEC-650: Upload a Web Shell to a Web Server
By exploiting insufficient permissions, it is possible to upload a web shell to a web server in such a way that it can be executed remotely. This shell can have various capabilities, thereby acting as a "gateway" to the underlying web server. The shell might execute at the higher permission level of the web server, providing the ability the execute malicious code at elevated levels.
CAPEC-94: Adversary in the Middle (AiTM)
An adversary targets the communication between two components (typically client and server), in order to alter or obtain data from transactions. A general approach entails the adversary placing themself within the communication channel between the two components.