Raw vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2026-35581 is a high-severity OS Command Injection (CWE-78) vulnerability in Nsa Emissary. Its CVSS base score is 7.2 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked at the 44th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-35581 is a command injection vulnerability (CWE-78) affecting Emissary, a peer-to-peer (P2P) based data-driven workflow engine. In versions prior to 8.39.0, the Executrix utility class constructs shell commands by directly concatenating configuration-derived values, including the PLACE_NAME parameter, with inadequate sanitization. This process only replaces spaces with underscores, allowing shell metacharacters such as ;, |, $, `, (, and ) to pass through unmodified into /bin/sh -c command execution.
The vulnerability carries a CVSS v3.1 base score of 7.2 (AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H), indicating network accessibility, low attack complexity, and the need for high privileges. Exploitation requires PR:H access, with no user interaction needed, and results in high impacts to confidentiality, integrity, and availability within the unchanged scope. An attacker with sufficient privileges could inject and execute arbitrary shell commands via specially crafted PLACE_NAME values, potentially leading to full system compromise.
The issue is addressed in Emissary version 8.39.0. Additional mitigation guidance is available in the GitHub security advisory at https://github.com/NationalSecurityAgency/emissary/security/advisories/GHSA-6c37-7w4p-jg9v.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-19730
Vulnerability Data
Emissary is a P2P based data-driven workflow engine. Prior to 8.39.0, the Executrix utility class constructed shell commands by concatenating configuration-derived values — including the PLACE_NAME parameter — with insufficient sanitization. Only spaces were replaced with underscores, allowing shell metacharacters…
more
(;, |, $, `, (, ), etc.) to pass through into /bin/sh -c command execution. This vulnerability is fixed in 8.39.0.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V1.2.5V1.2.8V15.2.5
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation can discover missing or incorrect command sanitization during development.
Input validation directly neutralizes or rejects special characters that would otherwise alter OS command structure.
Least privilege reduces the permissions available to any process that could be subverted by injected commands.
Least functionality restricts available OS commands and interpreters, limiting the blast radius of injection.
Secure engineering principles require proper neutralization of untrusted input before command construction.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
PR.PS-06's SDLC practices directly require secure coding and input handling that blocks command-injection defects, yet the single broad outcome leaves many specific neutralization vectors and verification gaps unaddressed.
Routine patching/maintenance can remediate known command-injection CVEs in dependencies (partial forward) but does nothing to stop developers from introducing improper neutralization in custom code (none reverse).
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.
Security testing and code review target insecure use of operating-system command interfaces, catching command-injection flaws introduced during development.