Is CVE-2026-118237 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-118237 being exploited in the wild.

How severe is CVE-2026-118237?

Informational severity, published 3 November 2026.

Which products and versions are affected?

GitHub Enterprise Server prior to 3.23; fixed in 3.22.3, 3.21.8, 3.20.10, 3.19.14.

Is there a fix for CVE-2026-118237?

Yes: fixed in GitHub Enterprise Server 3.22.3, 3.21.8, 3.20.10, 3.19.14. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-118237 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2026-118237?

Check whether you run GitHub Enterprise Server at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-118237: GitHub Enterprise Server out-of-bounds read in SSH key negotiation

CVE-2026-118237 · Severity: info · Published 2026-11-03

GitHub Enterprise Server contains an out-of-bounds memory read vulnerability in its SSH implementation that occurs during SSH key negotiation. An authenticated attacker with SSH access can trigger the vulnerability by re-keying to an algorithm with a longer hash, exposing adjacent process memory to the SSH client. While the amount of recoverable memory is limited, this could lead to disclosure of sensitive information stored in memory.

Technologies: GitHub Enterprise Server. Vendors: GitHub.

Quick answers

Is CVE-2026-118237 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-118237 being exploited in the wild.
How severe is CVE-2026-118237?: Informational severity, published 3 November 2026.
Which products and versions are affected?: GitHub Enterprise Server prior to 3.23; fixed in 3.22.3, 3.21.8, 3.20.10, 3.19.14.
Is there a fix for CVE-2026-118237?: Yes: fixed in GitHub Enterprise Server 3.22.3, 3.21.8, 3.20.10, 3.19.14. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-118237 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-118237?: Check whether you run GitHub Enterprise Server at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: GitHub Enterprise Server 3.22.3, 3.21.8, 3.20.10, 3.19.14

Technical details

The babeld SSH service component incorrectly sizes the session identifier based on the current digest length rather than the algorithm's own digest length during host key proof operations. An authenticated attacker can exploit this by initiating re-keying with a hash algorithm longer than the current one, causing an out-of-bounds read of adjacent process memory which is then cryptographically signed and returned to the client. The vulnerability affects all GitHub Enterprise Server versions prior to 3.23.

Affected products

GitHub Enterprise Server prior to 3.23; fixed in 3.22.3, 3.21.8, 3.20.10, 3.19.14

Timeline

2026-11-03: disclosed

References

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