Auth bypass in Github Enterprise Server

CVE-2021-22865

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.

EPSS: 0.013 (67.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-22865?
CVE-2021-22865 is a medium-severity vulnerability in Github Enterprise Server, classified under Improper Authorization. CVSS score: 6.5/10. Published 2021-04-02.
How severe is CVE-2021-22865?
Medium severity. CVSS v3 base score is 6.5 out of 10.