CVE-2026-78997

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.

CVSS v3.1 CNA

9.3 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

EPSS

0.40% chance of exploitation in the next 30 days, 33rd percentile

Published

2026-09-08

Updated

2026-09-09

Proof-of-concept exploits (1)

• Hunt-Benito/the-callback-that-outlived-the-page-cve-2026-78997-uc-browser-android-univers…0★ · 2026-09-11

References

• CVE Record
• NVD entry

Related

• CVE-2025-54328
• CVE-2026-102489
• CVE-2026-10672
• CVE-2026-11450
• CVE-2026-11451
• CVE-2026-11452