CVE-2026-109428
Raw vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/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-2026-109428 is a high-severity Interpretation Conflict (CWE-436) vulnerability. Its CVSS base score is 8.7 (High).
Operationally, ranked at the 42th 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.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-99221
Vulnerability Data
Mistral Vibe before 2.25.5 contains a permission validation bypass vulnerability that allows attackers to execute unauthorized commands by exploiting a parsing discrepancy between tree-sitter-bash and bash in handling backslash-newline line continuations in the _extract_commands() function of bash.py. Attackers can craft…
more
a command string where tree-sitter-bash extracts only an allowlisted prefix such as cd while bash joins the line continuation into a materially different and hidden command such as a curl request, causing resolve_permission to grant ALWAYS permission while bash executes unauthorized arbitrary commands.
- CWE(s)
AI Security AnalysisAI
- AI Category
- AI Agent Protocols and Integrations
- Risk Domain
- N/A
- OWASP Top 10 for LLMs 2025
- None mapped
- Classification Reason
- Matched keywords: mistral
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.