GitHub Enterprise Server up to 3.18.x/3.19.x/3.20.x/3.21.x Git service use after free

Summaryinfo

A vulnerability was found in GitHub Enterprise Server up to 3.18.x/3.19.x/3.20.x/3.21.x and classified as critical. Affected by this issue is some unknown functionality of the component Git service. Executing a manipulation can lead to use after free. This vulnerability is tracked as CVE-2026-104608. The attack can be launched remotely. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in GitHub Enterprise Server up to 3.18.x/3.19.x/3.20.x/3.21.x. It has been declared as critical. This vulnerability affects an unknown code of the component Git service. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

A remote code execution vulnerability was identified in GitHub Enterprise Server in the Git service (babeld). babeld held references into internal collections while calling into the SSH library, where a re-entrant callback could modify a collection and invalidate those references. An attacker with an account and SSH access to the instance could leverage this use-after-free into a controlled write and run arbitrary commands as babeld, including disclosure of its environment secrets. Exploitation required per-build memory offsets; failed attempts crashed babeld. This affected all releases prior to 3.23 and was fixed in 3.22.3, 3.21.8, 3.20.10, and 3.19.14. This vulnerability was reported via the GitHub Bug Bounty program.

The advisory is available at docs.github.com. This vulnerability was named CVE-2026-104608 since 10/02/2026. The exploitation appears to be easy. The attack can be initiated remotely. The technical details are unknown and an exploit is not available.

Upgrading to version 3.19.x, 3.20.x, 3.21.x or 3.22.x eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Bug Tracking Software

Vendor

• GitHub

Name

• Enterprise Server

Version

• 3.0
• 3.1
• 3.2
• 3.3
• 3.4
• 3.5
• 3.6
• 3.7
• 3.8
• 3.9
• 3.10
• 3.11
• 3.12
• 3.13
• 3.14
• 3.15
• 3.16
• 3.17
• 3.18
• 3.19
• 3.20
• 3.21

License

• open-source

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

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CVSSv3info

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Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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