Cyber Resilience

CVE-2026-59726

RCE

Published
09 July 2026
Modified
10 July 2026
CVSS Score v3.1 10.0
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.0044 36th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2026-59726 is a critical-severity OS Command Injection (CWE-78) vulnerability. Its CVSS base score is 10.0 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 36th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

This vulnerability is AI-related — categorised as AI Agent Protocols and Integrations; in the Protocol-Specific Risks risk domain.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and SC-7 (Boundary Protection) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Ruflo is an agent meta-harness for Claude Code and Codex. Prior to 3.16.3, ruflo's default docker-compose deployment exposed the MCP bridge POST /mcp and POST /mcp/:group endpoints without authentication, allowing an unauthenticated network attacker to invoke tools/call to terminal_execute, obtain…

more

a shell in the bridge container, read provider API keys, and poison AgentDB learning-store patterns. This issue is fixed in version 3.16.3.

CWE(s)

AI Security AnalysisAI

AI Category
AI Agent Protocols and Integrations
Risk Domain
Protocol-Specific Risks
OWASP Top 10 for LLMs 2025
None mapped
Classification Reason
Matched keywords: claude, mcp, mcp, mcp

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
T1078 Valid Accounts Stealth
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
T1552.001 Credentials In Files Credential Access
Adversaries may search local file systems and remote file shares for files containing insecurely stored credentials.
T1565.003 Runtime Data Manipulation Impact
Adversaries may modify systems in order to manipulate the data as it is accessed and displayed to an end user, thus threatening the integrity of the data.
Why these techniques?

Unauthenticated network-exposed endpoints (T1190) allow direct command execution via terminal_execute (T1059.004), access to stored credentials (T1552.001), and manipulation of learning-store data (T1565.003) without requiring valid accounts (T1078).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-44895Shared CWE-306, CWE-942
CVE-2026-34200Shared CWE-306, CWE-942
CVE-2026-46339Shared CWE-306, CWE-78
CVE-2026-57495Shared CWE-306
CVE-2026-55605Shared CWE-306
CVE-2026-22812Shared CWE-306, CWE-942
CVE-2025-59377Shared CWE-78
CVE-2024-12847Shared CWE-306, CWE-78
CVE-2026-36356Shared CWE-306, CWE-78
CVE-2026-45695Shared CWE-306, CWE-78

Affected Assets

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • AC-3 Access Enforcement
  • SC-7 Boundary Protection
  • AC-6 Least Privilege
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 6 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V3.4.3
  • V3.4.6
  • V6.2.3
  • V6.4.4

Mitigating Controls (NIST 800-53 r5) AI

prevent

Enforces authentication and authorization on the unauthenticated /mcp and /mcp/:group endpoints before any tool invocation or shell access can occur.

prevent

Places the MCP bridge behind a boundary-protection device or host-based firewall so that unauthenticated network traffic cannot reach the exposed POST endpoints.

prevent

Limits privileges inside the bridge container so that even if an attacker reaches terminal_execute, damage and key exposure are reduced.

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.AA-03 full match
prevents

Directly requires authentication of users/services/hardware, which eliminates missing authentication for critical functions.

PR.PS-01 mostly match
prevents

Hardened configuration baselines and reviews directly prevent permissive CSP or cross-domain policies.

PR.PS-06 mostly match
prevents

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.

ID.RA-01 partial match
prevents

Vulnerability identification processes can surface permissive policy misconfigurations.

PR.AA-01 partial match
prevents

Managing identities and credentials is a prerequisite for authentication but does not itself enforce it on critical functions.

PR.AA-05 partial match
prevents

Defining and enforcing authorizations assumes prior authentication and therefore only partially mitigates the absence of authentication.

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.

prevents

The control explicitly calls for authentication before any critical function is reached, eliminating the possibility of bypassing authentication for high-value operations.

detects

Security testing and code review target insecure use of operating-system command interfaces, catching command-injection flaws introduced during development.

prevents

Mandating authentication requirements for critical functions at the requirements-gathering stage ensures that essential operations are not left unprotected by missing login or verification mechanisms.

degrades

Network security policies can restrict cross-domain communication but do not specifically mandate strict CSP or cross-domain policy configuration.

mitigates

Mandating authentication for network services and critical functions stops attackers from invoking sensitive operations without credentials, closing gaps where authentication is absent for important capabilities.

degrades

Web filtering can block untrusted domains at the network level, partially mitigating permissive cross-domain policies.

References