Admidio is an open-source user management solution. Prior to version 5.0.9, the SAML IdP implementation in Admidio's SSO module uses the AssertionConsumerServiceURL value directly from incoming SAML AuthnRequest messages as the destination for the SAML response, without validating it against the registered ACS URL (smc_acs_url) stored in the database for the corresponding service provider client. An attacker who knows the Entity ID of a registered SP client can craft a SAML AuthnRequest with an arbitrary AssertionConsumerServiceURL, causing the IdP to send the signed SAML response -- containing user identity attributes (login name, email, roles, profile fields) -- to an attacker-controlled URL. This issue has been patched in version 5.0.9.
Metrics
Affected Vendors & Products
References
History
Thu, 07 May 2026 14:15:00 +0000
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ssvc
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Thu, 07 May 2026 05:45:00 +0000
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Admidio
Admidio admidio |
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Admidio
Admidio admidio |
Thu, 07 May 2026 04:15:00 +0000
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| Description | Admidio is an open-source user management solution. Prior to version 5.0.9, the SAML IdP implementation in Admidio's SSO module uses the AssertionConsumerServiceURL value directly from incoming SAML AuthnRequest messages as the destination for the SAML response, without validating it against the registered ACS URL (smc_acs_url) stored in the database for the corresponding service provider client. An attacker who knows the Entity ID of a registered SP client can craft a SAML AuthnRequest with an arbitrary AssertionConsumerServiceURL, causing the IdP to send the signed SAML response -- containing user identity attributes (login name, email, roles, profile fields) -- to an attacker-controlled URL. This issue has been patched in version 5.0.9. | |
| Title | Admidio: SAML Response Sent to Unvalidated Assertion Consumer Service URL from AuthnRequest | |
| Weaknesses | CWE-20 CWE-601 |
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| References |
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| Metrics |
cvssV3_1
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Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-05-07T13:44:01.169Z
Reserved: 2026-04-22T03:53:24.405Z
Link: CVE-2026-41670
Updated: 2026-05-07T13:43:49.583Z
Status : Deferred
Published: 2026-05-07T04:16:30.993
Modified: 2026-05-07T15:16:08.560
Link: CVE-2026-41670
No data.
OpenCVE Enrichment
Updated: 2026-05-07T05:45:06Z