CVE-2026-126398 vLLM 0.28.0 before 0.30.0 Denial of Service via Prompt Embeds on XD-RoPE Models

8.2 highEPSS 0.5%

High (8.2) in vllm-project vllm. EPSS 0.5% estimated probability of exploitation activity in the next 30 days.

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Affected
Versions
References
Your exposure

vLLM from 0.28.0 before 0.30.0 contains a reachable assertion vulnerability in GPUModelRunner._init_xdrope_positions that allows remote attackers to crash the engine by submitting embeddings-only requests. Attackers can send a /v1/completions request containing only prompt_embeds to XD-RoPE models with --enable-prompt-embeds, terminating the EngineCore and API server for all clients.

Severity

CVSS 4.0

8.2 high

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CVSS 3.1

5.9 medium

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS: 0.5% estimated probability of exploitation activity in the next 30 days; 43rd percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
CWE: CWE-617 Reachable Assertion
Published: 2026-11-13 10:17 UTC
Modified: 2026-11-13 10:17 UTC
Assigned by: VulnCheck (CNA)
NVD analysis: Awaiting analysis
Record from: the NVD, synced 2026-11-13 10:42 UTC

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Affected

vllm-project:vllm

Versions

From the CNA's record in the CVE List.

Product	Affected
vllm-project vllm	from 0.28.0 before 0.30.0

References

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