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CVE-2026-14340

An incorrect authorization vulnerability in GitHub Enterprise Server allows issue creation in unrelated public repositories

Published: Jul 1, 2026Updated: Jul 6, 2026 Sources: CVE List NVDCWE-863
5.0MEDIUM
NVD MITRE
EPSS Score
0.3%
Top 82.4%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
No Fix Available
Self-Check
OpenVAS

Description

An incorrect authorization vulnerability was identified in GitHub Enterprise Server that allowed a user-to-server token scoped to a GitHub App installation to perform certain write operations on public repositories outside the token's intended scope. This was possible because the authorization check only verified that the installation had read permissions on the target repository rather than verifying that the token's installation was explicitly granted access to that repository. An attacker who obtained a victim's user-to-server token could create issues, issue comments, commit comments, and private vulnerability reports on any public repository, appearing as the victim user with no indication of the app involvement. This vulnerability was fixed by adding a repository scope check for user-to-server tokens issued by global apps. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.21.2, 3.20.4, 3.19.8, 3.18.11, 3.17.17, 3.16.20. This vulnerability was reported via the GitHub Bug Bounty program.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:LUI:NS:CC:NI:LA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:CScope
Changed
Impact
C:NConfidentiality
None
I:LIntegrity
Low
A:NAvailability
None
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Weaknesses

CWE-863

Affected Products

GitHub
commercial·US
Enterprise Server
DevTools & CI
and 1 more affected products View all →

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques
Initial Access
View detailed technique mapping

References

https://docs.github.com/en/enterprise-server@3.16/admin/release-notes#3.16.20
docs.github.com
https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.17
docs.github.com
https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.11
docs.github.com
and 3 more references View all →

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