Firefox EUVD-2026-69077

User interaction is required (CVSS UI:R) - a victim must perform some action, such as visiting a malicious page or interacting with attacker-controlled browser automation content, for exploitation to succeed. From the attacker's side, no authentication or privileges are required (PR:N) and attack complexity is low (AC:L), meaning no special account or elaborate setup is needed. The attack vector is network-based (AV:N), so the attacker need not have local or adjacent access to the victim machine. The scope does not change (S:U), confining impact to the Firefox browser process itself rather than the underlying operating system. The primary exploitation limit is mandatory user interaction, which prevents fully automated exploitation without victim participation. The exact WebDriver BiDi configuration or feature state required to trigger the flaw is not explicitly specified in available data beyond the component identification.

At CVSS 8.8, this is a high-severity vulnerability with a network attack vector and low complexity, but the mandatory user interaction (UI:R) and SSVC 'Automatable: no' designation rule out fully automated, worm-style mass exploitation. SSVC reports 'Exploitation: none' and there is no CISA KEV listing, consistent with no observed in-the-wild abuse. Despite SSVC rating technical impact as total - reflecting full C/I/A compromise - the real-world urgency is high but scheduled: organizations should patch within their normal vulnerability management cycle rather than treating this as an incident-response trigger. No EPSS score is included in the available data; without it, exploitation probability cannot be quantified, and the absence of a public POC reinforces a lower immediate-exploitation-risk assessment. The primary gap between the high CVSS and moderate real-world urgency is the user interaction requirement, which limits attackers to scenarios where they can direct victims to malicious content.

An attacker hosts a malicious web page or automation endpoint that interacts with Firefox's WebDriver BiDi component through the improper access control flaw. When a victim user visits the page or triggers the interaction - consistent with the UI:R requirement - the attacker escalates privileges within the browser context, gaining full control over the browser process with high impact to confidentiality, integrity, and availability. No public exploit code is known at time of analysis.