CVE-2026-43629 ggml-org CVE debrief

Who should care

Defenders and security teams responsible for llama.cpp deployments, particularly those using builds b4882 through b9058, should assess their exposure and prioritize patching or mitigation. This vulnerability can lead to severe consequences, including potential arbitrary code execution, making immediate action crucial.

Why it matters

CVE-2026-43629 is a critical vulnerability in llama.cpp that allows attackers to corrupt heap memory, potentially leading to severe impacts like arbitrary code execution. Defenders should immediately assess exposure, prioritize patching, and implement compensating controls to mitigate the risk.

• Potential heap metadata corruption requiring urgent verification and remediation.
• Possible model weight corruption impacting AI model integrity and reliability.
• Risk of arbitrary code execution via function pointer overwrite, necessitating immediate patching.
• Need for compensating controls and monitoring due to limited visibility into exploitation.

Technical summary

The CVE-2026-43629 vulnerability in llama.cpp builds b4882 through b9058 is caused by a lack of overflow checking in the state_read_data() function, leading to a heap buffer overflow. This can be exploited by attackers with write access to the slot_save_path directory to corrupt heap memory, potentially resulting in heap metadata corruption, model weight corruption, or arbitrary code execution via function pointer overwrite. The vulnerability has a CVSS score of 9.2, indicating critical severity. Affected deployments should be identified, and owners assigned for follow-up. Official advisories and CVE records should be reviewed to validate affected scope, severity, and vendor guidance. Vendor-supported updates,

Defensive priority

High

Recommended defensive actions

• Immediately assess exposure of llama.cpp builds b4882 through b9058 in your environment.
• Verify if any compensating controls can mitigate the risk of exploitation.
• Prioritize patching or updating to a version outside the affected range (before b4882 or after b9058).
• Monitor for any suspicious activity related to the slot_save_path directory.
• Review and update incident response plans to address potential heap memory corruption.

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, including its critical CVSS score of 9.2 and affected versions of llama.cpp. The CVE Program and NIST National Vulnerability Database are the primary sources for this information.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.