CVE-2026-43631

llama.cpp builds b7492 through the latest b9060 contains a use-after-free vulnerability in the vocab pointer of llama-server when the --sleep-idle-seconds feature is enabled, allowing unauthenticated remote attackers to execute arbitrary code. Attackers can trigger the vulnerability by sending requests to affected endpoints while the server transitions to sleep mode, causing concurrent worker threads to dereference a freed vocab pointer that can be reclaimed with attacker-controlled data to achieve remote code execution.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/Vladimir-tokarev-cyera/llama-cpp-security-patches
https://www.vulncheck.com/advisories/llama-cpp-b7492-b9060-use-after-free-rce-via-llama-server

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-06 22:17

Updated : 2026-08-31 20:31

NVD link : CVE-2026-43631

Mitre link : CVE-2026-43631

CVE.ORG link : CVE-2026-43631

JSON object : View

Products Affected

No product.

CWE

CWE-362

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CWE-416

Use After Free

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