Bug 2512244 (CVE-2026-43632)

Summary:	CVE-2026-43632 llama.cpp: llama.cpp: Potential code execution via a race condition in tokenization endpoints
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	Keywords:	Security
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Hardware:	All
OS:	Linux
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Doc Text:	A flaw was found in llama.cpp. A use-after-free vulnerability exists in the llama-server's tokenization endpoints. This flaw allows a remote attacker to exploit a time-of-check-time-of-use race condition, where memory is freed by the main thread before an HTTP worker thread finishes using it. Successful exploitation could lead to a system crash or potentially arbitrary code execution.	Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2514852, 2514853, 2514854
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Description OSIDB Bzimport 2026-08-06 22:24:33 UTC

llama.cpp builds b7492 through the latest b9060 contains a use-after-free vulnerability in llama-server affecting six tokenization endpoints (/tokenize, /detokenize, /infill, /apply-template, /rerank, and /anthropic/count_tokens) that bypass the task queue and access ctx_server.vocab directly on HTTP worker threads. Attackers can exploit a time-of-check-time-of-use race condition where the main thread destroys and frees vocab after the synchronization lock is released but before the handler finishes using it, causing a crash or potential code execution when --sleep-idle-seconds is configured.