# CVE-2023-6004: Libssh: proxycommand/proxyjump features allow injection of malicious code through hostname

Status: published. Published: 2024-01-03. Updated: 2026-11-06.

A flaw was found in libssh. By utilizing the ProxyCommand or ProxyJump feature, users can exploit unchecked hostname syntax on the client. This issue may allow an attacker to inject malicious code into the command of the features mentioned through the hostname parameter.

## Remediation

- workaround: Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability. (source: CNA: redhat)

## Affected products and versions

- Red Hat / Red Hat Enterprise Linux 8 (libssh): ≥ 0:0.9.6-14.el8; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (libssh): ≥ 0:0.10.4-13.el9; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (libssh): Version range not reported. Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 4.8 (medium); CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:L; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 0.45% as of 2026-11-05; percentile 39.18%

- SSVC: exploitation none; automatable no; technical impact total; source ADP: CISA-ADP

- Weaknesses: CWE-74

## Exploit evidence

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

## References

- https://access.redhat.com/errata/RHSA-2024:2504 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:3233 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2023-6004 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2251110 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://www.libssh.org/security/advisories/CVE-2023-6004.txt (CNA: redhat)

- https://access.redhat.com/errata/RHSA-2024:2504 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:3233 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/security/cve/CVE-2023-6004 (ADP: CVE; vdb-entry, x_refsource_REDHAT, x_transferred)

- https://bugzilla.redhat.com/show_bug.cgi?id=2251110 (ADP: CVE; issue-tracking, x_refsource_REDHAT, x_transferred)

- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/LZQVUHWVWRH73YBXUQJOD6CKHDQBU3DM/ (ADP: CVE; x_transferred)

- https://security.netapp.com/advisory/ntap-20240223-0004/ (ADP: CVE; x_transferred)

- https://www.libssh.org/security/advisories/CVE-2023-6004.txt (ADP: CVE; x_transferred)

- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MKQRBF3DWMWPH36LBCOBUTSIZRTPEZXB/ (ADP: CVE)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2023-6004; retrieved 2026-11-06; source updated 2026-11-06

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2023-6004; retrieved 2026-11-06; source updated Not reported

Revision: 490e017871f1e50640e73cd090be2360582b2763c73c0ff707e2a6acf63c513d

Canonical: https://y2.dev/cve/CVE-2023-6004

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