CVE-2025-13476 (GCVE-0-2025-13476)

Vulnerability from cvelistv5 – Published: 2026-03-05 16:53 – Updated: 2026-03-06 10:36
VLAI
Title
Rakuten Viber uses broken or risky cryptographic Algorithm
Summary
Rakuten Viber Cloak mode in Android v25.7.2.0g and Windows v25.6.0.0–v25.8.1.0 uses a static and predictable TLS ClientHello fingerprint lacking extension diversity, allowing Deep Packet Inspection (DPI) systems to trivially identify and block proxy traffic, undermining censorship circumvention. (CWE-327)
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-06 10:34 UTC
CWE
Assigner
certcc CNA under the mitre root
CNA scorecard E 42/100 over 166 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Rakuten Viber Rakuten Viber Cloak - Android Affected: 25.7.2.0g , < 27.2.0.0g (custom)
guessed Create a notification for this product.
Rakuten Viber Rakuten Viber Cloak - Windows Affected: v25.6.0.0 , < v27.3.0.0 (custom)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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