How severe is CVE-2025-13476?

CVE-2025-13476 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-13476 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-13476?

CVE-2025-13476 primarily affects Rakuten Viber. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-13476?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2025-13476 have an EU (EUVD) identifier?

Yes. CVE-2025-13476 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-208314.

When was CVE-2025-13476 published?

CVE-2025-13476 was published on 2026-03-05 and last updated on 2026-06-17.

CVE-2025-13476

CVE-2025-13476 is a critical-severity vulnerability in Rakuten Viber with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-327.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 0% (26th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-208314
Weakness: CWE-327
Affected product: Rakuten Viber
Published: 2026-03-05
Last modified: 2026-06-17

Description

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)

Frequently asked questions

What is CVE-2025-13476?: 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)
How severe is CVE-2025-13476?: CVE-2025-13476 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-13476 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-13476?: CVE-2025-13476 primarily affects Rakuten Viber. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-13476?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2025-13476 have an EU (EUVD) identifier?: Yes. CVE-2025-13476 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-208314.
When was CVE-2025-13476 published?: CVE-2025-13476 was published on 2026-03-05 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:rakuten:viber:*:*:*:*:*:windows:*:*
cpe:2.3:a:rakuten:viber:9.3.0.6:25.7.2.0g:*:*:*:android:*:*

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