How severe is CVE-2018-20863?

CVE-2018-20863 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-2018-20863 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-20863?

CVE-2018-20863 affects Cpanel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-20863?

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-2018-20863 published?

CVE-2018-20863 was published on 2019-07-30 and last updated on 2026-06-17.

CVE-2018-20863

CVE-2018-20863 is a critical-severity vulnerability in Cpanel 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-20.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cpanel
Published: 2019-07-30
Last modified: 2026-06-17

Description

cPanel before 76.0.8 allows remote attackers to execute arbitrary code via mailing-list attachments (SEC-452).

Frequently asked questions

What is CVE-2018-20863?: cPanel before 76.0.8 allows remote attackers to execute arbitrary code via mailing-list attachments (SEC-452).
How severe is CVE-2018-20863?: CVE-2018-20863 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-2018-20863 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-20863?: CVE-2018-20863 affects Cpanel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-20863?: 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-2018-20863 published?: CVE-2018-20863 was published on 2019-07-30 and last updated on 2026-06-17.

References

https://documentation.cpanel.net/display/CL/76+Change+Log

Affected products (1)

cpe:2.3:a:cpanel:cpanel:*:*:*:*:*:*:*:*

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