CVE-2026-109434 (GCVE-0-2026-109434)

Vulnerability from cvelistv5 – Published: 2026-10-19 18:12 – Updated: 2026-10-19 18:36
VLAI
Title
Sleipnir Browser < 3.9.0 Fullscreen Address Bar Spoofing
Summary
Fenrir Sleipnir Browser for Android before 3.9.0 contains a UI spoofing vulnerability that allows remote attackers to impersonate the browser's trusted address bar by entering fullscreen mode via the Fullscreen API without displaying a persistent notification or trusted-origin indicator. Attackers can render a counterfeit address bar showing a trusted origin over attacker-controlled content after a single user tap, enabling credential harvesting, malware delivery, or social engineering through fake login, update, or payment pages.
Severity
5.1 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-19 18:36 UTC
CWE
  • CWE-451 - User Interface (UI) Misrepresentation of Critical Information
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6527 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Fenrir Sleipnir Mobile for Android Affected: 0 , < 3.9.0 (semver)
guessed Create a notification for this product.
Date Public
2026-10-15 00:00
Credits
Fanda Dwi Aprilianto
Show details on NVD website
To clipboard 

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