How severe is CVE-2021-38320?

CVE-2021-38320 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-2021-38320 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-38320?

CVE-2021-38320 affects Simplesamlphp Authentication Project Simplesamlphp Authentication. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-38320?

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

When was CVE-2021-38320 published?

CVE-2021-38320 was published on 2021-09-09 and last updated on 2026-06-17.

CVE-2021-38320

CVE-2021-38320 is a medium-severity vulnerability in Simplesamlphp Authentication Project Simplesamlphp Authentication 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% (58th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Simplesamlphp Authentication Project Simplesamlphp Authentication
Published: 2021-09-09
Last modified: 2026-06-17

Description

The simpleSAMLphp Authentication WordPress plugin is vulnerable to Reflected Cross-Site Scripting due to a reflected $_SERVER["PHP_SELF"] value in the ~/simplesamlphp-authentication.php file which allows attackers to inject arbitrary web scripts, in versions up to and including 0.7.0.

Frequently asked questions

What is CVE-2021-38320?: The simpleSAMLphp Authentication WordPress plugin is vulnerable to Reflected Cross-Site Scripting due to a reflected $_SERVER["PHP_SELF"] value in the ~/simplesamlphp-authentication.php file which allows attackers to inject arbitrary web scripts, in versions up to and including 0.7.0.
How severe is CVE-2021-38320?: CVE-2021-38320 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-2021-38320 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-38320?: CVE-2021-38320 affects Simplesamlphp Authentication Project Simplesamlphp Authentication. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-38320?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-38320 published?: CVE-2021-38320 was published on 2021-09-09 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:simplesamlphp_authentication_project:simplesamlphp_authentication:*:*:*:*:*:wordpress:*:*

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