Bug 2538419 (CVE-2026-94626)

Summary: CVE-2026-94626 vllm: vLLM: Denial of Service via unvalidated memory allocation parameter
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: alinfoot, bbrownin, dtrifiro, weaton
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in vLLM. A remote attacker can exploit a vulnerability in the `kv_transfer_params` function on OpenAI-compatible completion endpoints by supplying an unvalidated `tp_size` parameter. This allows for unbounded memory allocation, leading to memory exhaustion and a kernel Out-Of-Memory (OOM) kill of the decode worker process. This ultimately results in a Denial of Service (DoS) for the affected system.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-09-22 18:31:13 UTC 
vLLM through 0.29.0 fails to validate the tp_size parameter in kv_transfer_params on OpenAI-compatible completion endpoints, allowing attackers to allocate unbounded memory. Attackers can supply arbitrary tp_size values in prefill/decode disaggregated deployments to exhaust memory and trigger kernel OOM-kill of the decode worker process.