How severe is CVE-2015-5639?

CVE-2015-5639 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2015-5639 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2015-5639?

CVE-2015-5639 affects Dwango Niconico. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2015-5639?

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

When was CVE-2015-5639 published?

CVE-2015-5639 was published on 2017-10-10 and last updated on 2026-06-17.

CVE-2015-5639

CVE-2015-5639 is a high-severity vulnerability in Dwango Niconico with a CVSS 3.x base score of 7.4. 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-295.

Key facts

Severity: High (CVSS 3.x base score 7.4)
CVSS v2: 5.8
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Dwango Niconico
Published: 2017-10-10
Last modified: 2026-06-17

Description

niconico App for iOS before 6.38 does not verify SSL certificates which could allow remote attackers to execute man-in-the-middle attacks.

Frequently asked questions

What is CVE-2015-5639?: niconico App for iOS before 6.38 does not verify SSL certificates which could allow remote attackers to execute man-in-the-middle attacks.
How severe is CVE-2015-5639?: CVE-2015-5639 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2015-5639 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2015-5639?: CVE-2015-5639 affects Dwango Niconico. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2015-5639?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2015-5639 published?: CVE-2015-5639 was published on 2017-10-10 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:dwango:niconico:*:*:*:*:*:iphone_os:*:*

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