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

Status: published. Published: 2026-11-03. Updated: 2026-11-03.

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.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- GitHub / Enterprise Server: ≥ 3.19.0; < 3.19.* (affected, semver); unaffected at 3.19.14; ≥ 3.20.0; < 3.20.* (affected, semver); unaffected at 3.20.10; ≥ 3.21.0; < 3.21.* (affected, semver); unaffected at 3.21.8; ≥ 3.22.0; < 3.22.* (affected, semver); unaffected at 3.22.3. Source: CNA: GitHub_P

## Severity and prioritization

- CVSS 4.0: 5.3 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N; source: CNA: GitHub_P

- CVSS 4.0: 5.3 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X; source: NVD: product-cna@github.com

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-125

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.14 (CNA: GitHub_P; release-notes)

- https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.10 (CNA: GitHub_P; release-notes)

- https://docs.github.com/en/enterprise-server@3.21/admin/release-notes#3.21.8 (CNA: GitHub_P; release-notes)

- https://docs.github.com/en/enterprise-server@3.22/admin/release-notes#3.22.3 (CNA: GitHub_P; release-notes)

- https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.14 (product-cna@github.com)

- https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.10 (product-cna@github.com)

- https://docs.github.com/en/enterprise-server@3.21/admin/release-notes#3.21.8 (product-cna@github.com)

- https://docs.github.com/en/enterprise-server@3.22/admin/release-notes#3.22.3 (product-cna@github.com)

## Provenance

- CNA: GitHub_P: https://www.cve.org/CVERecord?id=CVE-2026-118237; retrieved 2026-11-03; source updated 2026-11-03

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-118237; retrieved 2026-11-04; source updated 2026-11-03

Revision: 9d862143c36aa9883aa5388d1ceceb2a1e45d637ce0d547172232c698ec523ab

Canonical: https://y2.dev/cve/CVE-2026-118237

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