CVE-2026-70556

Hubzilla versions prior to 11.4 contains a cross-site request forgery vulnerability in the OAuth2 /authorize endpoint handled by Zotlabs\Module\Authorize::post() that allows unauthenticated attackers to register arbitrary OAuth2 applications under an authenticated user's account by submitting a cross-origin POST request without CSRF token or Origin/Referer validation. Attackers can craft a malicious HTML form that autosubmits attacker-chosen OAuth2 parameters including client_id, client_secret, redirect_uri, and scope to silently register a persistent OAuth2 application, enabling interception of future OAuth2 authorization codes when the victim later authenticates against the attacker-controlled client.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://framagit.org/hubzilla/core
https://framagit.org/hubzilla/core/-/blob/dev/Zotlabs/Module/Authorize.php?ref_type=heads#L49
https://hub.volse.no/cloud/harald/Skjermopptak_20260616_095037.webm
https://www.vulncheck.com/advisories/hubzilla-csrf-via-oauth2-authorize-endpoint-app-registration
https://hub.volse.no/cloud/harald/Skjermopptak_20260616_095037.webm

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-06 13:18

Updated : 2026-08-13 21:18

NVD link : CVE-2026-70556

Mitre link : CVE-2026-70556

CVE.ORG link : CVE-2026-70556

JSON object : View

Products Affected

No product.

CWE

CWE-352

Cross-Site Request Forgery (CSRF)

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