CVE-2025-13476

Rakuten Viber uses broken or risky cryptographic Algorithm

Critical · published March 5, 2026

CVSS v3.1
9.8
EPSS
0%
Percentile
29.3
In the wild
Unconfirmed
What it is

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)

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00366 · 29.3th percentile
Published
2026-03-05T16:53Z
EPSS history
Timeline
  • 05 MAR 16:53Z
    Rakuten Viber uses broken or risky cryptographic Algorithm
    cvelistv5