GitHub Enterprise Server up to 3.19.1 Repository Migration Upload Endpoint authorization

Summaryinfo

A vulnerability identified as problematic has been detected in GitHub Enterprise Server up to 3.19.1. This issue affects some unknown processing of the component Repository Migration Upload Endpoint. The manipulation leads to authorization. This vulnerability is documented as CVE-2026-1355. The attack can be initiated remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in GitHub Enterprise Server up to 3.19.1. This issue affects some unknown functionality of the component Repository Migration Upload Endpoint. The manipulation with an unknown input leads to a authorization vulnerability. Using CWE to declare the problem leads to CWE-862. The product does not perform an authorization check when an actor attempts to access a resource or perform an action. Impacted is integrity, and availability. The summary by CVE is:

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 identifier, an attacker could overwrite or replace a victim’s migration archive, potentially causing victims to download attacker-controlled repository data during migration restores or automated imports. An attacker would require authentication to the victim's GitHub Enterprise Server instance. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.20 and was fixed in versions 3.19.2, 3.18.5, 3.17.11, 3.16.14, 3.15.18, 3.14.23. This vulnerability was reported via the GitHub Bug Bounty program.

The weakness was released by ahacker1. It is possible to read the advisory at docs.github.com. The identification of this vulnerability is CVE-2026-1355 since 01/22/2026. The exploitation is known to be easy. The attack may be initiated remotely. The technical details are unknown and an exploit is not publicly available.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-0460). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Microsoft GitHub Enterprise

Productinfo

Type

• Bug Tracking Software

Vendor

• GitHub

Name

• Enterprise Server

Version

• 3.14.0
• 3.14.1
• 3.14.2
• 3.14.3
• 3.14.4
• 3.14.5
• 3.14.6
• 3.14.7
• 3.14.8
• 3.14.9
• 3.14.10
• 3.14.11
• 3.14.12
• 3.14.13
• 3.14.14
• 3.14.15
• 3.14.16
• 3.14.17
• 3.14.18
• 3.14.19
• 3.14.20
• 3.14.21
• 3.14.22
• 3.15.0
• 3.15.1
• 3.15.2
• 3.15.3
• 3.15.4
• 3.15.5
• 3.15.6
• 3.15.7
• 3.15.8
• 3.15.9
• 3.15.10
• 3.15.11
• 3.15.12
• 3.15.13
• 3.15.14
• 3.15.15
• 3.15.16
• 3.15.17
• 3.16.0
• 3.16.1
• 3.16.2
• 3.16.3
• 3.16.4
• 3.16.5
• 3.16.6
• 3.16.7
• 3.16.8
• 3.16.9
• 3.16.10
• 3.16.11
• 3.16.12
• 3.16.13
• 3.17.0
• 3.17.1
• 3.17.2
• 3.17.3
• 3.17.4
• 3.17.5
• 3.17.6
• 3.17.7
• 3.17.8
• 3.17.9
• 3.17.10
• 3.18.0
• 3.18.1
• 3.18.2
• 3.18.3
• 3.18.4
• 3.19.0
• 3.19.1

License

• open-source

CPE 2.3info

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CPE 2.2info

• 🔒
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Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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