How severe is CVE-2018-0691?

CVE-2018-0691 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2018-0691 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-0691?

CVE-2018-0691 primarily affects Kddi + Message. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-0691?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2018-0691 published?

CVE-2018-0691 was published on 2018-11-15 and last updated on 2026-06-17.

CVE-2018-0691

CVE-2018-0691 is a medium-severity vulnerability in Kddi + Message with a CVSS 3.x base score of 5.9. 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: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 1% (47th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Kddi + Message
Published: 2018-11-15
Last modified: 2026-06-17

Description

Multiple +Message Apps (Softbank +Message App for Android prior to version 10.1.7, Softbank +Message App for iOS prior to version 1.1.23, NTT DOCOMO +Message App for Android prior to version 42.40.2800, NTT DOCOMO +Message App for iOS prior to version 1.1.23, KDDI +Message App for Android prior to version 1.0.6, and KDDI +Message App for iOS prior to version 1.1.23) do not verify X.509 certificates from SSL servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.

Frequently asked questions

What is CVE-2018-0691?: Multiple +Message Apps (Softbank +Message App for Android prior to version 10.1.7, Softbank +Message App for iOS prior to version 1.1.23, NTT DOCOMO +Message App for Android prior to version 42.40.2800, NTT DOCOMO +Message App for iOS prior to version 1.1.23, KDDI +Message App for Android prior to version 1.0.6, and KDDI +Message App for iOS prior to version 1.1.23) do not verify X.509 certificates from SSL servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.
How severe is CVE-2018-0691?: CVE-2018-0691 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2018-0691 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-0691?: CVE-2018-0691 primarily affects Kddi + Message. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-0691?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-0691 published?: CVE-2018-0691 was published on 2018-11-15 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:kddi:\+_message:*:*:*:*:*:*:*:*
cpe:2.3:a:ntttocomo:\+_message:*:*:*:*:*:*:*:*
cpe:2.3:a:softbank:\+_message:*:*:*:*:*:*:*:*
cpe:2.3:a:ntt_tocomo:\+_message:*:*:*:*:*:*:*:*

More vulnerabilities in Kddi + Message

CVE-2022-43543 — Medium (CVSS 5.4): KDDI +Message App, NTT DOCOMO +Message App, and SoftBank +Message App contain a vulnerability caused by improper…

All CVEs affecting Kddi + Message →

Other CWE-295 (Improper Certificate Validation) vulnerabilities

CVE-2026-4370 — Critical (CVSS 10.0): A vulnerability was identified in Juju from version 3.2.0 until 3.6.19 and from version 4.0 until 4.0.4, where the…
CVE-2026-30836 — Critical (CVSS 10.0): Step CA is an online certificate authority for secure, automated certificate management for DevOps. Versions 0.30.0-rc6…
CVE-2025-68121 — Critical (CVSS 10.0): During session resumption in crypto/tls, if the underlying Config has its ClientCAs or RootCAs fields mutated between…
CVE-2022-20703 — Critical (CVSS 10.0): Multiple vulnerabilities in Cisco Small Business RV160, RV260, RV340, and RV345 Series Routers could allow an attacker…
CVE-2021-1471 — Critical (CVSS 9.9): Multiple vulnerabilities in Cisco Jabber for Windows, Cisco Jabber for MacOS, and Cisco Jabber for mobile platforms…
CVE-2026-20184 — Critical (CVSS 9.8): A vulnerability in the integration of single sign-on (SSO) with Control Hub in Cisco Webex Services could have allowed…

Browse all CWE-295 (Improper Certificate Validation) vulnerabilities →