How severe is CVE-2021-31803?

CVE-2021-31803 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-2021-31803 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-31803?

CVE-2021-31803 affects Cpanel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-31803?

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

When was CVE-2021-31803 published?

CVE-2021-31803 was published on 2021-04-26 and last updated on 2026-06-17.

CVE-2021-31803

CVE-2021-31803 is a medium-severity vulnerability in Cpanel 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: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Cpanel
Published: 2021-04-26
Last modified: 2026-06-17

Description

cPanel before 94.0.3 allows self-XSS via EasyApache 4 Save Profile (SEC-581).

Frequently asked questions

What is CVE-2021-31803?: cPanel before 94.0.3 allows self-XSS via EasyApache 4 Save Profile (SEC-581).
How severe is CVE-2021-31803?: CVE-2021-31803 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-2021-31803 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-31803?: CVE-2021-31803 affects Cpanel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-31803?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-31803 published?: CVE-2021-31803 was published on 2021-04-26 and last updated on 2026-06-17.

References

https://docs.cpanel.net/changelogs/94-change-log/

Affected products (1)

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

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