CVE-2021-22865 | Improper access control in GitHub Enterprise Server leading to unauthorized read access to private repository metadata

An improper access control vulnerability was identified in GitHub Enterprise Server that allowed access tokens generated from a GitHub App's web authentication flow to read private repository metadata via the REST API without having been granted the appropriate permissions. 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. The private repository metadata returned would be limited to repositories owned by the user the token identifies. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.0.4 and was fixed in versions 3.0.4, 2.22.10, 2.21.18. This vulnerability was reported via the GitHub Bug Bounty program.

Published: 2021-04-02 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-22865 is rated Moderate Risk (50.5/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.32%). EPSS rose +1.09% over the last day, indicating growing attacker interest. Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-22865

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.23% 1.32% +1.09%
2 2025-03-30 0.44% 0.23% -0.21%
3 2025-03-29 — 0.44% —

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-22865

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 3.6 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2021-22865

Affected software / configurations for CVE-2021-22865

Vendor Product Version Raw CPE
github enterprise_server < 2.21.18 cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*
github enterprise_server >= 2.22.0, < 2.22.10 cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*
github enterprise_server >= 3.0.0, < 3.0.4 cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*

References for CVE-2021-22865

cvelogic Threat Intelligence