CVE-2023-6004
Libssh 0.8.0 – 0.9.8
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:LCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2023-6004 is a medium-severity Injection (CWE-74) vulnerability in Libssh Libssh. Its CVSS base score is 4.8 (Medium).
Operationally, ranked at the 38th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) — see the control section below for these in your framework.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-58271
Vulnerability Data
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…
more
the hostname parameter.
- CWE(s)
Related Threats
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
SI-10 directly requires validation of information inputs to reject malformed or special-element content before it reaches downstream parsers.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Logging supports detection of injection attempts but does not prevent the weakness.
Monitoring activities can identify active injection attacks after they occur.
A.8.25 mandates a secure SDLC process that includes secure coding guidelines, security requirements, checkpoints, testing (scans/penetration), and developer training to reduce injection flaws, but does not itself enforce or guarantee neutralization of special elements at runtime.
Application security requirements explicitly call for controls against injection attacks in software design.
A.8.27 mandates security-by-design principles (including distrust external input, data validation/sanitization, secure architecture layers, and design reviews against attack patterns) that reach injection when applied to output construction; this stops exploitation for a minority slice (e.g. where principles drive sanitization) but leaves most code-level injection defects untouched without further implementation rigor.
Secure coding standards require proper neutralization of special elements, directly addressing CWE-74.
Hardening callouts derived
DISA STIG baselines are authored against specific weaknesses. Where this CVE cites a broad weakness class, the mapping is not asserted at that abstraction (owner ruling, 2026-09-25: grade only at Base and below), so no rule is shown here rather than a rule shown against the wrong grain.
- No fine-grained STIG row for CWE-74, a class-level weakness, and none of its children carries one either.