Bug 2558029 (CVE-2026-114049)

Summary: CVE-2026-114049 vllm: vLLM: Output manipulation via stale token filter reuse in batch processing
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: alinfoot, bbrownin, dtrifiro, mwoodson, 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 compromise the integrity of responses generated for other users by submitting concurrent constrained generation requests. Due to improper state cleanup during batch reorganization, restriction rules defining permitted response tokens can persist in recycled memory slots. As a result, an attacker's token restrictions can be inadvertently enforced on unrelated client requests, improperly constraining their model outputs.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-10-21 01:01:53 UTC
vLLM before 0.31.0 contains a cross-request mask leak in InputBatch.condense() that allows remote attackers to constrain other clients' outputs by leaving stale allowed_token_ids rows. Attackers can submit concurrent constrained generate requests, including via unauthenticated /invocations, so recycled batch slots apply their token allowlist to victims' unrestricted requests.