CVE-2021-22866Network attack vector

Unintended permission grants via incomplete reauthorization display

Published May 14, 2021 · Updated Aug 3, 2024

GitHub Enterprise Server 2.22.0 through 2.22.12 and 3.0.0 through 3.0.6 has UI misrepresentation allowing attackers unintended permissions. The GitHub App reauthorization screen omits newly requested user-level permissions in certain revisits while the authorization flow still grants them. Exploitation requires an attacker-created GitHub App and a user who authorized it once to revisit the flow after the app adds permissions, exposing resources covered by the undisclosed grants.

CVSS severity8.8
High
EPSS probability1.04%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

GitHub Enterprise Server 2.22.0 through 2.22.12 and 3.0.0 through 3.0.6 has UI misrepresentation allowing attackers unintended permissions. The GitHub App reauthorization screen omits newly requested user-level permissions in certain revisits while the authorization flow still grants them. Exploitation requires an attacker-created GitHub App and a user who authorized it once to revisit the flow after the app adds permissions, exposing resources covered by the undisclosed grants.

The record

CVE
CVE-2021-22866
Published
May 14, 2021
Updated
Aug 3, 2024
Vendor
Twitter
Product
GitHub Enterprise Server
Classifications
CWE-1021, CWE-451
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 14, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.22 <2.22.13
  2. Affected versionversion=3.0 <3.0.7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Twitter · GitHub Enterprise Serverversion=2.22 <2.22.13; version=3.0 <3.0.7

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

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

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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