TYPO3 AI Integration EUVD-2026-104864

The TYPO3 'typo3_ai_integration_extension' must be installed and active, and the attacker must hold any valid backend user session (PR:L) - no administrator or elevated role is needed, but anonymous/front-end access is not sufficient. The vulnerable backend endpoint accepts attacker-controlled page UID, field name, and value and performs neither a permission check nor a field allowlist, so no special product configuration is required beyond having the extension present. The principal limiting factor is the authentication requirement (a provisioned backend account) and the extension's restricted deployment footprint; there is no required user interaction and no non-default setting needed.

The vendor-supplied CVSS 4.0 vector (AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:H/VA:L) scores 7.2 (High) and is internally consistent with the description: the flaw is reachable over the network (AV:N), is trivial to trigger (AC:L/AT:N), requires only a low-privileged authenticated backend account (PR:L), needs no victim interaction (UI:N), and its dominant impact is integrity (VI:H) because an attacker can overwrite any field of any page record - including access permissions and configuration - effectively enabling vertical privilege escalation and unauthorized access to restricted content (hence the VC:L and VA:L secondary impacts). No EPSS probability, SSVC decision, KEV listing, or POC indicator was provided in the input, so there is no public exploit identified at time of analysis and no evidence of active exploitation; the risk rating rests on severity, not demonstrated use. Two factors meaningfully cap real-world risk: exploitation requires a valid backend user (PR:L, not PR:N), and the vulnerable component is a specific, non-core TYPO3 add-on rather than TYPO3 core, so the exposed population is limited to installations that have deployed this particular AI integration extension. For organizations that do run it, however, this is a genuine priority because the barrier (any backend login) is low and the integrity impact (rewriting page ACLs) is high. Note: CWE-862 (Missing Authorization) describes a broken-access-control/authorization flaw by an already-authenticated user, which conflicts with the 'Authentication Bypass' tag applied in the input - authentication is not bypassed.

A low-privileged but authenticated TYPO3 backend user (e.g. a limited editor) sends a crafted request to the extension's unprotected write endpoint, supplying a target page UID, a sensitive field name such as the page's access/permission setting, and an attacker-chosen value. Because the endpoint performs no permission check and does not restrict which fields may be modified, the user rewrites the access controls of a page outside their granted scope, escalating their effective privileges. No public exploit code was identified in the provided data; exploitation is straightforward given AV:N/AC:L and only PR:L.