Vulnerabilities fixed in GitHub Enterprise Server

GitHub has fixed vulnerabilities in GitHub Enterprise Server Specifically for versions before 3.20, 3.19.2, 3.18.5 and 3.17.11. The first vulnerability concerns an authorization issue that allowed attackers to merge unauthorized pull-requests into repositories that provide fork support. The secon...

CVE-2026-1355

A Missing Authorization vulnerability was identified in GitHub Enterprise Server that allowed an attacker to upload unauthorized content to another user’s repository migration export due to a missing authorization check in the repository migration upload endpoint. By supplying the migration...

CVE-2026-1999

An incorrect authorization vulnerability was identified in GitHub Enterprise Server that allowed an attacker to merge their own pull request into a repository without having push access by exploiting an authorization bypass in the enableautomerge mutation for pull requests. This issue only affect...

CVE-2026-1999

A Server-Side Request Forgery SSRF vulnerability was identified in GitHub Enterprise Server that allowed an authenticated user to access internal services bound to loopback or unspecified addresses, potentially disrupting background job processing, accessing administrative endpoints, metrics, and...

CVE-2026-1999

An incorrect authorization vulnerability was identified in GitHub Enterprise Server that allowed an attacker to merge their own pull request into a repository without having push access by exploiting an authorization bypass in the enableautomerge mutation for pull requests. This issue only affect...

CVE-2026-1355

A Missing Authorization vulnerability was identified in GitHub Enterprise Server that allowed an attacker to upload unauthorized content to another user’s repository migration export due to a missing authorization check in the repository migration upload endpoint. By supplying the migration...

CVE-2026-1355

A Missing Authorization vulnerability was identified in GitHub Enterprise Server that allowed an attacker to upload unauthorized content to another user’s repository migration export due to a missing authorization check in the repository migration upload endpoint. By supplying the migration...

CVE-2026-0573

An URL redirection vulnerability was identified in GitHub Enterprise Server that allowed attacker-controlled redirects to leak sensitive authorization tokens. The repositorypages API insecurely followed HTTP redirects when fetching artifact URLs, preserving the authorization header containing a...

CVE-2026-1999 Incorrect Authorization vulnerability was identified in GitHub Enterprise Server that allowed unauthorized merging of pull requests

An incorrect authorization vulnerability was identified in GitHub Enterprise Server that allowed an attacker to merge their own pull request into a repository without having push access by exploiting an authorization bypass in the enableautomerge mutation for pull requests. This issue only affect...

CVE-2026-1999 Incorrect Authorization vulnerability was identified in GitHub Enterprise Server that allowed unauthorized merging of pull requests

An incorrect authorization vulnerability was identified in GitHub Enterprise Server that allowed an attacker to merge their own pull request into a repository without having push access by exploiting an authorization bypass in the enableautomerge mutation for pull requests. This issue only affect...

CVE-2026-1999

A Server-Side Request Forgery SSRF vulnerability was identified in GitHub Enterprise Server that allowed an authenticated user to access internal services bound to loopback or unspecified addresses, potentially disrupting background job processing, accessing administrative endpoints, metrics, and...

CVE-2026-1999

CVE-2026-1999 affects GitHub Enterprise Server and is an incorrect authorization vulnerability in the enable_auto_merge mutation for pull requests. An attacker could merge their own PR into a repository without push access under specific conditions: the repository must allow forking, a clean PR s...

CVE-2026-1355 Missing Authorization Check in GitHub Enterprise Server Allows Unauthorized Uploads to Repository Migration Exports

A Missing Authorization vulnerability was identified in GitHub Enterprise Server that allowed an attacker to upload unauthorized content to another user’s repository migration export due to a missing authorization check in the repository migration upload endpoint. By supplying the migration...

CVE-2026-1355 Missing Authorization Check in GitHub Enterprise Server Allows Unauthorized Uploads to Repository Migration Exports

A Missing Authorization vulnerability was identified in GitHub Enterprise Server that allowed an attacker to upload unauthorized content to another user’s repository migration export due to a missing authorization check in the repository migration upload endpoint. By supplying the migration...

CVE-2026-1355

GitHub Enterprise Server contains a Missing Authorization vulnerability in the repository migration upload endpoint. An authenticated attacker could supply a migration identifier to overwrite or replace a victim’s migration archive, potentially causing victims to download attacker-controlled repo...

CVE-2026-0573 Improper Handling of HTTP Redirects vulnerability was identified in GitHub Enterprise Server that allowed leaking of authorization token and enabled remote code execution

An URL redirection vulnerability was identified in GitHub Enterprise Server that allowed attacker-controlled redirects to leak sensitive authorization tokens. The repositorypages API insecurely followed HTTP redirects when fetching artifact URLs, preserving the authorization header containing a...

CVE-2026-0573

CVE-2026-0573 affects GitHub Enterprise Server. The repository_pages API insecurely follows HTTP redirects when fetching artifact URLs, preserving the Authorization header containing a privileged JWT. An authenticated user could redirect requests to an attacker-controlled domain, exfiltrate the A...

CVE-2026-0573 Improper Handling of HTTP Redirects vulnerability was identified in GitHub Enterprise Server that allowed leaking of authorization token and enabled remote code execution

An URL redirection vulnerability was identified in GitHub Enterprise Server that allowed attacker-controlled redirects to leak sensitive authorization tokens. The repositorypages API insecurely followed HTTP redirects when fetching artifact URLs, preserving the authorization header containing a...

PT-2026-20503

Name of the Vulnerable Software and Affected Versions GitHub Enterprise Server versions prior to 3.20 GitHub Enterprise Server versions 3.19.2 through 3.19.2 GitHub Enterprise Server versions 3.18.5 through 3.18.5 GitHub Enterprise Server versions 3.17.11 through 3.17.11 GitHub Enterprise Server...

PT-2026-20495

Name of the Vulnerable Software and Affected Versions GitHub Enterprise Server versions prior to 3.19 GitHub Enterprise Server versions 3.19.2 GitHub Enterprise Server versions 3.18.4 GitHub Enterprise Server versions 3.17.10 GitHub Enterprise Server versions 3.16.13 GitHub Enterprise Server...