How severe is CVE-2018-15556?

CVE-2018-15556 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-2018-15556 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-15556?

CVE-2018-15556 affects Actiontec Web6000q Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-15556?

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.

When was CVE-2018-15556 published?

CVE-2018-15556 was published on 2019-06-27 and last updated on 2026-06-17.

CVE-2018-15556

CVE-2018-15556 is a critical-severity vulnerability in Actiontec Web6000q Firmware 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-287.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 3% (88th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Actiontec Web6000q Firmware
Published: 2019-06-27
Last modified: 2026-06-17

Description

The Quantenna WiFi Controller on Telus Actiontec WEB6000Q v1.1.02.22 allows login with root level access with the user "root" and an empty password by using the enabled onboard UART headers.

Frequently asked questions

What is CVE-2018-15556?: The Quantenna WiFi Controller on Telus Actiontec WEB6000Q v1.1.02.22 allows login with root level access with the user "root" and an empty password by using the enabled onboard UART headers.
How severe is CVE-2018-15556?: CVE-2018-15556 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-2018-15556 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-15556?: CVE-2018-15556 affects Actiontec Web6000q Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-15556?: 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.
When was CVE-2018-15556 published?: CVE-2018-15556 was published on 2019-06-27 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:actiontec:web6000q_firmware:1.1.02.22:*:*:*:*:*:*:*

More vulnerabilities in Actiontec Web6000q Firmware

CVE-2018-15555 — Critical (CVSS 9.8): On Telus Actiontec WEB6000Q v1.1.02.22 devices, an attacker can login with root level access with the user "root" and…
CVE-2018-15557 — High (CVSS 8.8): An issue was discovered in the Quantenna WiFi Controller on Telus Actiontec WEB6000Q v1.1.02.22 devices. An attacker…

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