CVE-2026-109331
Raw vector
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/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:XCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2026-109331 is a high-severity Interpretation Conflict (CWE-436) vulnerability. Its CVSS base score is 7.5 (High).
Operationally, ranked at the 3th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
This vulnerability is AI-related — categorised as AI Agent Protocols and Integrations; in the Protocol-Specific Risks risk domain.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-97633
Vulnerability Data
Network-AI from 5.14.0 before 5.15.2 contains a security control bypass vulnerability in the ClaudeHookBridge PreToolUse hook, which matches deny patterns only against the first present candidate field. A prompt-injected agent can place dangerous payloads in fields like Write content or…
more
an MCP script parameter beside a benign file_path or command, evading denyPatterns to write web shells or execute scripts.
- 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
- AI-specific weaknesses CR
- CWE-1427 — Prompt injection bypasses denyPatterns via untrusted input reaching model.
Mapped by Cyber Resilience · not in NVD. Poisoning and extraction cases are routed to MITRE ATLAS instead of a synthetic CWE.- Classification Reason
- Matched keywords: ai, mcp
Related Threats
CVEs Like This One
Affected Assets
Mitigating Controls
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.
A.8.25 mandates a secure SDLC process with checkpoints, secure coding, testing and training; it does not stop differing interpretations of shared state or inputs between two products from arising or being exploited
A.8.26 only requires that security requirements (including resilience against injections or input controls) be identified and specified during development or acquisition; it does not itself enforce, implement or assure any mechanism that stops an interpretation conflict from being exploitable.
A.8.27 establishes and applies secure-by-design principles (defense-in-depth, least privilege, assume-breach, distrust-external-input, hardening, etc.) but does not stop two products from interpreting the same input or protocol step differently; the resulting state/conflict weakness can still be present and exploitable.
Secure coding standards can enforce canonical input handling and strict protocol compliance to avoid misinterpretation between products.
Security testing can detect and correct cases where one component misinterprets another’s state or messages.
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-436, a class-level weakness, and none of its children carries one either.