How severe is CVE-2021-26715?

CVE-2021-26715 has a CVSS 3.x base score of 9.1, 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 none.

Is CVE-2021-26715 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26715?

CVE-2021-26715 affects Mitreid Connect. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-26715?

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-2021-26715 published?

CVE-2021-26715 was published on 2021-03-25 and last updated on 2026-06-17.

CVE-2021-26715

CVE-2021-26715 is a critical-severity vulnerability in Mitreid Connect with a CVSS 3.x base score of 9.1. 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-918.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
CVSS v2: 6.4
EPSS exploit prediction: 1% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-918
Affected product: Mitreid Connect
Published: 2021-03-25
Last modified: 2026-06-17

Description

The OpenID Connect server implementation for MITREid Connect through 1.3.3 contains a Server Side Request Forgery (SSRF) vulnerability. The vulnerability arises due to unsafe usage of the logo_uri parameter in the Dynamic Client Registration request. An unauthenticated attacker can make a HTTP request from the vulnerable server to any address in the internal network and obtain its response (which might, for example, have a JavaScript payload for resultant XSS). The issue can be exploited to bypass network boundaries, obtain sensitive data, or attack other hosts in the internal network.

Frequently asked questions

What is CVE-2021-26715?: The OpenID Connect server implementation for MITREid Connect through 1.3.3 contains a Server Side Request Forgery (SSRF) vulnerability. The vulnerability arises due to unsafe usage of the logo_uri parameter in the Dynamic Client Registration request. An unauthenticated attacker can make a HTTP request from the vulnerable server to any address in the internal network and obtain its response (which might, for example, have a JavaScript payload for resultant XSS). The issue can be exploited to bypass network boundaries, obtain sensitive data, or attack other hosts in the internal network.
How severe is CVE-2021-26715?: CVE-2021-26715 has a CVSS 3.x base score of 9.1, 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 none.
Is CVE-2021-26715 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26715?: CVE-2021-26715 affects Mitreid Connect. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-26715?: 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-2021-26715 published?: CVE-2021-26715 was published on 2021-03-25 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:mitreid:connect:*:*:*:*:*:*:*:*

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