GitHub Enterprise Server up to 3.21.2 Delegated Bypass Endpoint authorization

Summaryinfo

A vulnerability, which was classified as problematic, was found in GitHub Enterprise Server up to 3.17.17/3.18.11/3.19.8/3.20.4/3.21.2. The affected element is an unknown function of the component Delegated Bypass Endpoint. The manipulation results in authorization. This vulnerability is identified as CVE-2026-15783. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability classified as problematic has been found in GitHub Enterprise Server up to 3.17.17/3.18.11/3.19.8/3.20.4/3.21.2. Affected is some unknown functionality of the component Delegated Bypass Endpoint. The manipulation with an unknown input leads to a authorization vulnerability. CWE is classifying the issue as CWE-862. The product does not perform an authorization check when an actor attempts to access a resource or perform an action. This is going to have an impact on confidentiality. CVE summarizes:

A missing authorization vulnerability was identified in GitHub Enterprise Server that allowed an authenticated user with write access to any repository to read metadata from private repositories they did not have access to, including private repository owners and names, branch names, commit SHAs, commit messages, and the pushing actor. The delegated bypass endpoint resolved a rule suite directly from an attacker-supplied, encoded identifier without verifying that the requesting user could read the rule suite's repository, and because these identifiers are sequential an attacker could enumerate them across the instance. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.17.18, 3.18.12, 3.19.9, 3.20.5, and 3.21.3. This vulnerability was reported via the GitHub Bug Bounty program.

The advisory is shared for download at docs.github.com. This vulnerability is traded as CVE-2026-15783 since 07/14/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. There are neither technical details nor an exploit publicly available.

Upgrading to version 3.17.18, 3.18.12, 3.19.9, 3.20.5 or 3.21.3 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Bug Tracking Software

Vendor

• GitHub

Name

• Enterprise Server

Version

• 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
• 3.17.11
• 3.17.12
• 3.17.13
• 3.17.14
• 3.17.15
• 3.17.16
• 3.17.17
• 3.18.0
• 3.18.1
• 3.18.2
• 3.18.3
• 3.18.4
• 3.18.5
• 3.18.6
• 3.18.7
• 3.18.8
• 3.18.9
• 3.18.10
• 3.18.11
• 3.19.0
• 3.19.1
• 3.19.2
• 3.19.3
• 3.19.4
• 3.19.5
• 3.19.6
• 3.19.7
• 3.19.8
• 3.20.0
• 3.20.1
• 3.20.2
• 3.20.3
• 3.20.4
• 3.21.0
• 3.21.1
• 3.21.2

License

• open-source

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

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Once again VulDB remains the best source for vulnerability data.

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