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Fencer Intel
high 8.8

CVE-2021-22866 json

UI misrepresentation of granted permissions in GitHub Enterprise Server leading to unauthorized access to user resources

published 5y ago modified 4mo ago also EUVD-2021-10001

cvss
8.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
1.0%
EPSS 1.0% chance of exploitation in 30 days, percentile 64%
public exploits
0
none known

Summary

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.

Patch / fix

  • GitHub GitHub Enterprise Server 2.22.13, 3.0.7

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Exploit prediction

1.05% chance of exploitation in the next 30 days, higher than 64% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD 2.0 6.8 AV:N/AC:M/Au:N/C:P/I:P/A:P

Affected products

  • GitHub GitHub Enterprise Server

Classification

Weakness
  • CWE-451 User Interface (UI) Misrepresentation of Critical Information
  • CWE-1021 Improper Restriction of Rendered UI Layers or Frames

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.