CVE-2026-78997

critical

Description

UC Browser for Android (package com.UCMobile.intl, version 13.7.8.1314) contains a Universal Cross-Site Scripting vulnerability that allows an attacker to execute arbitrary JavaScript in the context of any origin. An attacker hosts a specially crafted URL on a UC-owned domain (via a reflected XSS) that leverages the browser's internal JavaScript bridge to register a deferred callback, navigate the tab to a victim site, and then execute attacker-controlled code on that site when a login dialog is dismissed.

References

https://gist.github.com/OmriInbar-Novee/ef7a92db148b2eb1ab0aa7b99a565c4c

https://gist.github.com/OmriInbar-Novee/9fd65fe08c1b1cff6a19350e44425de2

Details

Source: Mitre, NVD

Published: 2026-09-08

Updated: 2026-09-09

Risk Information

CVSS v2

Base Score: 9.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:N

Severity: High

CVSS v3

Base Score: 9.3

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

Severity: Critical

EPSS

EPSS: 0.00153