Vulnerability from drupal
This module enables you to turn a Drupal install into the Central Authentication System (CAS) Server. It makes your database the primary location for other systems to use for authentication in a SSO environment.
The module doesn't sufficiently check the service URL used to redirect the user during logout, leading to an open redirect.
This vulnerability is mitigated by the fact that an attacker must convince a user to click a specially crafted link. The vulnerability cannot be exploited without user interaction and does not allow an attacker to directly compromise the CAS server or bypass authentication.
| URL | Type | |
|---|---|---|
{
"affected": [
{
"database_specific": {
"affected_versions": "\u003c2.0.4 || \u003e=2.1.0 \u003c2.1.3"
},
"package": {
"ecosystem": "Packagist:https://packages.drupal.org/8",
"name": "drupal/cas_server"
},
"ranges": [
{
"database_specific": {
"constraint": "\u003c2.0.4"
},
"events": [
{
"introduced": "0"
},
{
"fixed": "2.0.4"
}
],
"type": "ECOSYSTEM"
},
{
"database_specific": {
"constraint": "\u003e=2.1.0 \u003c2.1.3"
},
"events": [
{
"introduced": "2.1.0"
},
{
"fixed": "2.1.3"
}
],
"type": "ECOSYSTEM"
}
],
"severity": []
}
],
"aliases": [
"CVE-2026-87937"
],
"credits": [
{
"contact": [
"https://www.drupal.org/u/kekkis"
],
"name": "Kalle Kipin\u00e4 (kekkis)"
}
],
"details": "This module enables you to turn a Drupal install into the Central Authentication System (CAS) Server. It makes your database the primary location for other systems to use for authentication in a SSO environment.\n\nThe module doesn\u0027t sufficiently check the service URL used to redirect the user during logout, leading to an open redirect.\n\nThis vulnerability is mitigated by the fact that an attacker must convince a user to click a specially crafted link. The vulnerability cannot be exploited without user interaction and does not allow an attacker to directly compromise the CAS server or bypass authentication.",
"id": "DRUPAL-CONTRIB-2026-135",
"modified": "2026-09-09T17:15:40.000Z",
"published": "2026-09-09T17:15:40.000Z",
"references": [
{
"type": "WEB",
"url": "https://www.drupal.org/sa-contrib-2026-135"
}
],
"schema_version": "1.7.0"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.