CVE-2026-9132
Missing authorization vulnerability in GitHub Enterprise Server allowed disclosure of private repository contents via the Copilot pull request diff summary endpoint
Description
A missing authorization vulnerability was identified in GitHub Enterprise Server that allowed an authenticated user to read source code from private repositories they did not have access to. The Copilot pull request description diff summary endpoint accepted a cross-repository comparison range and rendered the resulting diff without verifying that the requesting user was authorized to view the target repository. Exploitation required an authenticated account on the instance with read access to at least one repository to use as the comparison base. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.21 and was fixed in versions 3.17.17, 3.18.11, 3.19.8, and 3.20.4. This vulnerability was reported via the GitHub Bug Bounty program.
INFO
Published Date :
June 30, 2026, 9:16 p.m.
Last Modified :
July 2, 2026, 3:35 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | MEDIUM | 82327ea3-741d-41e4-88f8-2cf9e791e760 | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update to version 3.17.17 or later.
- Update to version 3.18.11 or later.
- Update to version 3.19.8 or later.
- Update to version 3.20.4 or later.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-9132.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-9132 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-9132
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-9132 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-9132 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Jul. 02, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N Added CPE Configuration OR *cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:* versions from (including) 3.18.0 up to (excluding) 3.18.11 *cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:* versions from (including) 3.19.0 up to (excluding) 3.19.8 *cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:* versions from (including) 3.20.0 up to (excluding) 3.20.4 *cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:* versions up to (excluding) 3.17.17 Added Reference Type GitHub, Inc. (Products Only): https://docs.github.com/en/[email protected]/admin/release-notes#3.17.17-features Types: Release Notes Added Reference Type GitHub, Inc. (Products Only): https://docs.github.com/en/[email protected]/admin/release-notes#3.18.11-features Types: Release Notes Added Reference Type GitHub, Inc. (Products Only): https://docs.github.com/en/[email protected]/admin/release-notes#3.19.8-features Types: Release Notes Added Reference Type GitHub, Inc. (Products Only): https://docs.github.com/en/[email protected]/admin/release-notes#3.20.4-features Types: Release Notes -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jul. 01, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-9132', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-01T15:37:41.106015Z'} -
New CVE Received by [email protected]
Jun. 30, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'GitHub', 'product': 'Enterprise Server', 'versions': [{'status': 'affected', 'changes': [{'at': '3.17.17', 'status': 'unaffected'}], 'version': '3.17.0', 'versionType': 'semver', 'lessThanOrEqual': '3.17.16'}, {'status': 'affected', 'changes': [{'at': '3.18.11', 'status': 'unaffected'}], 'version': '3.18.0', 'versionType': 'semver', 'lessThanOrEqual': '3.18.10'}, {'status': 'affected', 'changes': [{'at': '3.19.8', 'status': 'unaffected'}], 'version': '3.19.0', 'versionType': 'semver', 'lessThanOrEqual': '3.19.7'}, {'status': 'affected', 'changes': [{'at': '3.20.4', 'status': 'unaffected'}], 'version': '3.20.0', 'versionType': 'semver', 'lessThanOrEqual': '3.20.3'}], 'defaultStatus': 'unaffected'}] Added Description A missing authorization vulnerability was identified in GitHub Enterprise Server that allowed an authenticated user to read source code from private repositories they did not have access to. The Copilot pull request description diff summary endpoint accepted a cross-repository comparison range and rendered the resulting diff without verifying that the requesting user was authorized to view the target repository. Exploitation required an authenticated account on the instance with read access to at least one repository to use as the comparison base. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.21 and was fixed in versions 3.17.17, 3.18.11, 3.19.8, and 3.20.4. This vulnerability was reported via the GitHub Bug Bounty program. Added CVSS V4.0 AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-862 Added Reference https://docs.github.com/en/[email protected]/admin/release-notes#3.17.17-features Added Reference https://docs.github.com/en/[email protected]/admin/release-notes#3.18.11-features Added Reference https://docs.github.com/en/[email protected]/admin/release-notes#3.19.8-features Added Reference https://docs.github.com/en/[email protected]/admin/release-notes#3.20.4-features