How severe is CVE-2020-18671?

CVE-2020-18671 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2020-18671 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-18671?

CVE-2020-18671 affects Roundcube Webmail. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-18671?

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

When was CVE-2020-18671 published?

CVE-2020-18671 was published on 2021-06-24 and last updated on 2026-06-17.

CVE-2020-18671

CVE-2020-18671 is a medium-severity vulnerability in Roundcube Webmail with a CVSS 3.x base score of 5.4. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v2: 3.5
EPSS exploit prediction: 1% (53rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Roundcube Webmail
Published: 2021-06-24
Last modified: 2026-06-17

Description

Cross Site Scripting (XSS) vulnerability in Roundcube Mail <=1.4.4 via smtp config in /installer/test.php.

Frequently asked questions

What is CVE-2020-18671?: Cross Site Scripting (XSS) vulnerability in Roundcube Mail <=1.4.4 via smtp config in /installer/test.php.
How severe is CVE-2020-18671?: CVE-2020-18671 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2020-18671 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-18671?: CVE-2020-18671 affects Roundcube Webmail. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-18671?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-18671 published?: CVE-2020-18671 was published on 2021-06-24 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:roundcube:webmail:*:*:*:*:*:*:*:*

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