How severe is CVE-2018-15476?

CVE-2018-15476 has a CVSS 3.x base score of 8.1, 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 high.

Is CVE-2018-15476 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-15476?

CVE-2018-15476 primarily affects Mystrom Wifi Switch Firmware. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-15476?

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-2018-15476 published?

CVE-2018-15476 was published on 2018-08-30 and last updated on 2026-06-17.

CVE-2018-15476

CVE-2018-15476 is a high-severity vulnerability in Mystrom Wifi Switch Firmware with a CVSS 3.x base score of 8.1. 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 8.1)
CVSS v2: 9.3
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Mystrom Wifi Switch Firmware
Published: 2018-08-30
Last modified: 2026-06-17

Description

An issue was discovered in myStrom WiFi Switch V1 before 2.66, WiFi Switch V2 before 3.80, WiFi Switch EU before 3.80, WiFi Bulb before 2.58, WiFi LED Strip before 3.80, WiFi Button before 2.73, and WiFi Button Plus before 2.73. The SSL/TLS server certificate in the device to cloud communication was not verified by the device. As a result, an attacker in control of the network traffic of a device could have taken control of a device by intercepting and modifying commands issued from the server to the device in a Man-in-the-Middle attack. This included the ability to inject firmware update commands into the communication and cause the device to install maliciously modified firmware.

Frequently asked questions

What is CVE-2018-15476?: An issue was discovered in myStrom WiFi Switch V1 before 2.66, WiFi Switch V2 before 3.80, WiFi Switch EU before 3.80, WiFi Bulb before 2.58, WiFi LED Strip before 3.80, WiFi Button before 2.73, and WiFi Button Plus before 2.73. The SSL/TLS server certificate in the device to cloud communication was not verified by the device. As a result, an attacker in control of the network traffic of a device could have taken control of a device by intercepting and modifying commands issued from the server to the device in a Man-in-the-Middle attack. This included the ability to inject firmware update commands into the communication and cause the device to install maliciously modified firmware.
How severe is CVE-2018-15476?: CVE-2018-15476 has a CVSS 3.x base score of 8.1, 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 high.
Is CVE-2018-15476 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-15476?: CVE-2018-15476 primarily affects Mystrom Wifi Switch Firmware. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-15476?: 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-2018-15476 published?: CVE-2018-15476 was published on 2018-08-30 and last updated on 2026-06-17.

References

https://www.swisscom.ch/content/dam/swisscom/de/about/nachhaltigkeit/digitale-schweiz/sicherheit/bug-bounty/files/cve-2018-15476ff.txt

Affected products (6)

cpe:2.3:o:mystrom:wifi_switch_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mystrom:wifi_button_plus_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mystrom:wifi_button_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mystrom:wifi_switch_eu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mystrom:wifi_bulb_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mystrom:wifi_led_strip_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Mystrom Wifi Switch Firmware

CVE-2018-15477 — Critical (CVSS 9.8): myStrom WiFi Switch V1 devices before 2.66 did not sanitize a parameter received from the cloud that was used in an OS…
CVE-2018-15480 — High (CVSS 8.8): An issue was discovered in myStrom WiFi Switch V1 before 2.66, WiFi Switch V2 before 3.80, WiFi Switch EU before 3.80,…
CVE-2018-15478 — High (CVSS 8.1): An issue was discovered in myStrom WiFi Switch V1 before 2.66, WiFi Switch V2 before 3.80, WiFi Switch EU before 3.80,…
CVE-2018-15479 — Medium (CVSS 6.5): An issue was discovered in myStrom WiFi Switch V1 before 2.66, WiFi Switch V2 before 3.80, WiFi Switch EU before 3.80,…

All CVEs affecting Mystrom Wifi Switch Firmware →

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 →