CVE-2026-118237 Out-of-bounds read vulnerability in GitHub Enterprise Server allowed disclosure of process memory in the Git service

Description

An out-of-bounds read vulnerability was identified in GitHub Enterprise Server in the Git service (babeld). When proving possession of a host key, babeld's SSH implementation sized the session identifier by the current digest length rather than its own. An attacker with an account and SSH access could re-key to an algorithm with a longer hash, causing adjacent process memory to be signed and returned to the client, where a limited amount of it may be recoverable. This vulnerability affected all releases prior to 3.23 and was fixed in versions 3.22.3, 3.21.8, 3.20.10, and 3.19.14. This vulnerability was reported via the GitHub Bug Bounty program.

Exploitable remotely over the network, with an ordinary account and without any user action; the impact on data or service is limited.

Attack vector

Network

Attack complexity

Low

Attack requirements

None

Privileges required

Low

Interaction

None

Confidentiality

Low

Integrity

None

Availability

None

Confidentiality of other systems

None

Integrity of other systems

None

Availability of other systems

None

Affected products and versions