6.5Medium

CVE-2026-86550

NuBrowser lacks protocol whitelist validation for the S.browser_fallback_url field of intent://, allowing attackers to inject javascript: URLs via 302 redirects. This results in a universal cross‑site scripting (UXSS) vulnerability that enables script execution within the origin of arbitrary websites.

What this means for your business

  • An attacker can use it remotely, over a network, without a login, but only after tricking someone into an action such as opening a file or a link.
  • FIRST's prediction model gives it a 0.3% chance of attack attempts being seen in the next 30 days, ranking above 19% of all known flaws.

What to do

  1. 1Ask your IT team or provider whether any of your systems use the affected product.
  2. 2If you do, follow the vendor's guidance. No patch reference has been published yet.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

Scoring

CVSS
6.5 (v3.1)
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Weakness
CWE-79
Assigned by
psirt@zte.com.cn

Dates

Published
2026-09-08
Last modified
2026-09-09
Sources
NVD

References