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TI-2026-51649 Aliases CVE-2026-73559GHSA-87x5-vmc3-756j

vLLM: Completion prompt lists fan out into unbounded engine requests

Priority MEDIUM 62CWE-400Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 2 fixed, 1 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-400.

Summary

vLLM is an inference and serving engine for large language models. From 0.19.0 until 0.26.0, the /v1/completions CompletionRequest.prompt field in vllm/entrypoints/openai/completion/protocol.py accepts an unbounded list[str] or list[list[int]], prompt_to_seq() in vllm/renderers/inputs/preprocess.py and OnlineRenderer.preprocess_completion() in vllm/renderers/online_renderer.py expand every element, and vllm/entrypoints/openai/completion/serving.py creates one engine generator and response slot per prompt, allowing an authenticated API client to exhaust CPU, memory, async scheduling capacity, engine request slots, and response buffering with one request. This issue is fixed in version 0.26.0.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00583 48th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial vllm (vllm-project): 0.26.0vllm (PyPI): 0.26.0Red Hat: 7 advisoriesRed Hat: 2 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
vllm-projectvllm0.19.0 to before 0.26.00.26.0Patch availableCNA
—vllm (PyPI)0.19.0 to before 0.26.00.26.0Patch availableGHSA-87x5-vmc3-756j
  • vllm Vendorvllm-project Affected 0.19.0 to before 0.26.0 Fixed in 0.26.0 Patch available CNA
  • vllm (PyPI) Vendor— Affected 0.19.0 to before 0.26.0 Fixed in 0.26.0 Patch available GHSA-87x5-vmc3-756j

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:vllm:vllm:*:*:*:*:*:*:*:*0.19.0 to before 0.26.0VulnerablevLLM
  • cpe:2.3:a:vllm:vllm:*:*:*:*:*:*:*:* Versions 0.19.0 to before 0.26.0 Vulnerable ·vLLM

Remediation

  • Fix · CNA vllm (vllm-project) Fixed in 0.26.0
  • Fix · GHSA-87x5-vmc3-756j vllm (PyPI) Fixed in 0.26.0 Advisory →

Red Hat 7 advisories

  • RHSA-2026:92452 Released 2026-10-29 · Red Hat rating Critical
    Red Hat Enterprise Linux AI 3.5.2 enhancement update
    • Red Hat Enterprise Linux AI 3.5 registry.redhat.io/rhelai3/bootc-aws-cuda-rhel9, registry.redhat.io/rhelai3/bootc-azure-cuda-rhel9, registry.redhat.io/rhelai3/bootc-azure-rocm-rhel9 +3
  • RHSA-2026:92449 Released 2026-10-29 · Red Hat rating Critical
    Red Hat Enterprise Linux AI 3.5.2 enhancement update
    • Red Hat Enterprise Linux AI 3.5 registry.redhat.io/rhelai3/disk-image-cuda-rhel9
  • RHSA-2026:82415 Released 2026-10-13 · Red Hat rating Critical
    Red Hat AI Inference 3.5.2 (cpu)
    • Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-cpu-rhel9
Show 4 more Red Hat advisories
  • RHSA-2026:82371 Released 2026-10-13 · Red Hat rating Critical
    Red Hat AI Inference 3.5.2 (spyre)
    • Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-spyre-rhel9
  • RHSA-2026:82368 Released 2026-10-13 · Red Hat rating Critical
    Red Hat AI Inference 3.5.2 (cuda)
    • Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-cuda-rhel9
  • RHSA-2026:82061 Released 2026-10-13 · Red Hat rating Critical
    Red Hat AI Inference Tech Preview 3.5.2 (Gaudi)
    • Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-gaudi-rhel9
  • RHSA-2026:82059 Released 2026-10-13 · Red Hat rating Critical
    Red Hat AI Inference 3.5.2 (ROCm)
    • Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-rocm-rhel9

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat OpenShift AI (RHOAI)AffectedNo fix yet: Fix deferred
Red Hat AI Inference Server 3.5Fixed RHSA-2026:82059, RHSA-2026:82061, RHSA-2026:82368, RHSA-2026:82371, RHSA-2026:82415
Red Hat Enterprise Linux AI 3.5Fixed RHSA-2026:92449, RHSA-2026:92452
Not affected: 3 products
  • Red Hat AI Inference Server
  • Red Hat Enterprise Linux AI (RHEL AI) 3
  • Red Hat OpenShift AI (RHOAI)

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-73559
  2. 2026-10-03 Alias added: GHSA-87x5-vmc3-756j
  3. 2026-10-06 Affected versions changed · Red Hat
  4. 2026-10-13 Fix available: RHSA-2026:82061 · Red Hat
  5. 2026-10-13 Fix available: RHSA-2026:82059 · Red Hat
  6. 2026-10-13 Fix available: Red Hat AI Inference Server 3.5 · Red Hat
  7. 2026-10-14 Fix available: RHSA-2026:82368 · Red Hat
  8. 2026-10-14 Fix available: RHSA-2026:82415 · Red Hat
  9. 2026-10-14 Fix available: RHSA-2026:82371 · Red Hat
  10. 2026-10-15 Affected versions changed · Red Hat
  11. 2026-10-30 Fix available: RHSA-2026:92452 · Red Hat
  12. 2026-10-30 Fix available: RHSA-2026:92449 · Red Hat
  13. 2026-10-30 Fix available: Red Hat Enterprise Linux AI 3.5 · Red Hat

References

Exploit 1

Patch 2

Advisory 1

Other 2

  • TI-2024-10229 Remote Code Execution in vllm-project/vllm CVSS 3.0CRITICAL 9.8
  • TI-2024-08404 Remote Code Execution in vllm-project/vllm CVSS 3.1CRITICAL 9.8
  • TI-2026-36017 vLLM: OpenAI auth bypass CVSS 3.1CRITICAL 9.1
  • TI-2026-63056 vLLM before 0.28.0 Denial of Service via negative token ID CVSS 4.0HIGH 8.7
  • TI-2026-04308 Hardcoded trust_remote_code=True in vllm-project/vllm Bypasses User Security Control CVSS 3.0HIGH 8.8
  • TI-2026-39137 vLLM: Remote DoS in vLLM via Invalid Recovered Token Reinjection CVSS 3.1HIGH 7.5
See all 124 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences