How severe is CVE-2018-17866?

CVE-2018-17866 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2018-17866 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-17866?

CVE-2018-17866 affects Ultimatemember Ultimate Member. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-17866?

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

When was CVE-2018-17866 published?

CVE-2018-17866 was published on 2018-10-09 and last updated on 2026-06-17.

CVE-2018-17866

CVE-2018-17866 is a medium-severity vulnerability in Ultimatemember Ultimate Member with a CVSS 3.x base score of 6.1. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 2% (74th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Ultimatemember Ultimate Member
Published: 2018-10-09
Last modified: 2026-06-17

Description

Multiple cross-site scripting (XSS) vulnerabilities in includes/core/um-actions-login.php in the "Ultimate Member - User Profile & Membership" plugin before 2.0.28 for WordPress allow remote attackers to inject arbitrary web script or HTML via the "Primary button Text" or "Second button text" field.

Frequently asked questions

What is CVE-2018-17866?: Multiple cross-site scripting (XSS) vulnerabilities in includes/core/um-actions-login.php in the "Ultimate Member - User Profile & Membership" plugin before 2.0.28 for WordPress allow remote attackers to inject arbitrary web script or HTML via the "Primary button Text" or "Second button text" field.
How severe is CVE-2018-17866?: CVE-2018-17866 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2018-17866 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-17866?: CVE-2018-17866 affects Ultimatemember Ultimate Member. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-17866?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-17866 published?: CVE-2018-17866 was published on 2018-10-09 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:ultimatemember:ultimate_member:*:*:*:*:*:wordpress:*:*

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