Is CVE-2021-22866 actively exploited?

No active exploitation of CVE-2021-22866 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2021-22866 be exploited remotely?

Yes. CVE-2021-22866 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2021-22866?

CVE-2021-22866 has a CVSS score of 8.8 (HIGH).

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HIGH

CVE-2021-22866

CWE-451Published: May 14, 2021· Updated: Jun 17, 2026

8.8

CVSS v3.1

Official Description

A UI misrepresentation vulnerability was identified in GitHub Enterprise Server that allowed more permissions to be granted during a GitHub App's user-authorization web flow than was displayed to the user during approval. To exploit this vulnerability, an attacker would need to create a GitHub App on the instance and have a user authorize the application through the web authentication flow. All permissions being granted would properly be shown during the first authorization, but in certain circumstances, if the user revisits the authorization flow after the GitHub App has configured additional user-level permissions, those additional permissions may not be shown, leading to more permissions being granted than the user potentially intended. This vulnerability affected GitHub Enterprise Server 3.0.x prior to 3.0.7 and 2.22.x prior to 2.22.13. It was fixed in versions 3.0.7 and 2.22.13. This vulnerability was reported via the GitHub Bug Bounty program.

NVD Source

Technical Analysis

CVE-2021-22866 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 8.8.