GitHub Enterprise Server patches SSH and Dependabot flaws in four lines

GitHub Enterprise Server patches SSH and Dependabot flaws in four lines

3 November 2026: GitHub has released Enterprise Server 3.19.14, 3.20.10, 3.21.8 and 3.22.3 with two high-severity security fixes. The first is a use-after-free in SSH session handling that lets an authenticated user with SSH access run commands as the Git service, babeld, and read its environment secrets. The second completes an earlier fix for Dependabot, which could write files into protected repository paths, Actions workflows included.

Not yet independently verified. Three of the four CVE numbers are shown by GitHub as requested rather than assigned. GitHub's release notes do not say whether any of the flaws has been exploited. We will update this when it can be confirmed, and remove this note.

Every supported line before those releases is affected. Canada's Cyber Centre repeated the advisory on 4 November.

Two high-severity paths to secrets

The babeld flaw (CVE-2026-104608, requested) needs a valid account with SSH access, and it is not easy. GitHub says the attacker needs memory offsets specific to the build, and a failed attempt kills babeld, which interrupts Git over SSH for everyone on the appliance. A crash of that service during a quiet period is worth a look in the logs.

The Dependabot flaw (CVE-2026-15343) needs code execution inside a Dependabot updater container, the place a poisoned dependency would run during an update. From there it could write files to repository paths it should not touch, including workflow files, where the installation has workflows: write permission. An injected workflow could then reach the repository's Actions secrets. GitHub says the earlier fix for this was incomplete.

The medium fixes and a kernel mitigation

Two medium-severity fixes ship in the same releases:

• babeld reads past the session identifier while re-keying to a longer-hash algorithm, leaking a limited amount of process memory (CVE-2026-118237, requested);
• the ChatOps settings and credentials for Slack and Teams could be deleted through a cross-site request forgery against a signed-in Management Console operator (CVE-2026-110288, requested).

The releases also add a mitigation for the Linux TCP flaw CVE-2026-98432: the appliance firewall now drops IPv4 TCP SYN packets that carry IP options, and MPTCP is disabled. GitHub says a fixed kernel will come in a later release. Bundled components including Go, Node.js, Ruby, OpenSSL and curl are updated, and GitHub notes that CVE-2026-111943 is only partly addressed.

Planning the upgrade

The fixed builds by line:

• 3.19: 3.19.14;
• 3.20: 3.20.10;
• 3.21: 3.21.8;
• 3.22: 3.22.3.

Teams that cannot upgrade at once can review which installations of Dependabot hold workflows: write and which accounts have SSH keys, since both flaws start from access an attacker must already have. Our DevOps software category lists 17 products.

Sources

• GitHub Docs: Enterprise Server 3.22 release notes, 3.22.3 (3 November 2026), 3 November 2026
• GitHub Docs: Enterprise Server 3.19 release notes, 3.19.14 (3 November 2026), 3 November 2026
• Canadian Centre for Cyber Security: GitHub security advisory (AV26-1126), 4 November 2026