---
id: CVE-2026-71486
title: vLLM is an inference and serving engine for large language models
summary: >-
  vLLM is an inference and serving engine for large language models. Prior to
  0.26.0, the /v1/completions/derender and /v1/chat/completions/derender
  endpoints accept caller-supplied GenerateResponse objects whose
  generate_responses, choice…
severity: medium
cvss: 4.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L'
cwe:
  - CWE-400
  - CWE-770
vendor: vllm
product: vllm
affected:
  - vllm < 0.26.0
patched:
  - vllm 0.26.0
published: '2026-08-17'
updated: '2026-10-02'
sourceUpdated: '2026-10-02T19:30:34.767'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-71486'
references:
  - url: >-
      https://github.com/vllm-project/vllm/commit/8e61b646e2d157f9b93451fa048f9c8530c8a67b
    label: security-advisories@github.com
  - url: 'https://github.com/vllm-project/vllm/pull/47260'
    label: security-advisories@github.com
  - url: 'https://github.com/vllm-project/vllm/releases/tag/v0.26.0'
    label: security-advisories@github.com
  - url: >-
      https://github.com/vllm-project/vllm/security/advisories/GHSA-8737-qx52-hjff
    label: security-advisories@github.com
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-71486'
  - url: 'https://github.com/advisories/GHSA-8737-qx52-hjff'
  - url: 'https://github.com/vllm-project/vllm'
  - url: 'https://pypi.org/project/vllm'
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-71486.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-71486'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2517595'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-71486'
  - url: 'https://access.redhat.com/errata/RHSA-2026:82415'
  - url: 'https://access.redhat.com/errata/RHSA-2026:82368'
  - url: 'https://access.redhat.com/errata/RHSA-2026:82061'
  - url: 'https://access.redhat.com/errata/RHSA-2026:82059'
  - url: 'https://access.redhat.com/errata/RHSA-2026:82371'
tags:
  - nvd
  - ghsa
  - pip
  - osv
  - exploit-available
  - csaf
  - vex
  - red-hat
epss: 0.00374
epssPercentile: 0.31147
aliases:
  - GHSA-8737-qx52-hjff
  - PYSEC-2026-3936
ecosystem: pip
ingestedAt: '2026-09-04T22:28:54.993Z'
exploitAvailable: true
---

## Overview

vLLM is an inference and serving engine for large language models. Prior to 0.26.0, the /v1/completions/derender and /v1/chat/completions/derender endpoints accept caller-supplied GenerateResponse objects whose generate_responses, choices, token_ids, prompt_logprobs, logprobs.content, top_logprobs, and routed_experts structures are processed by OnlineDerenderer and tokenizer.decode before max_model_len, max_tokens, max_num_seqs, or response-size limits are enforced, allowing an authenticated API client to consume excessive CPU and memory and produce oversized responses. This issue is fixed in version 0.26.0.

## Affected

- `vllm < 0.26.0`

## Remediation

Upgrade past the affected range:

- `vllm 0.26.0`

## Package advisory (CVE-2026-71486)

Affected packages:

- `vllm < 0.26.0`

Patched in:

- `vllm 0.26.0`

Source: https://github.com/advisories/GHSA-8737-qx52-hjff

## Vendor advisories

- **RHSA-2026:82415** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82415)
- **RHSA-2026:82368** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82368)
- **RHSA-2026:82061** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82061)
- **RHSA-2026:82059** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82059)
- **RHSA-2026:82371** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82371)
- **Red Hat VEX** · Moderate · affected: Red Hat AI Inference Server, Red Hat Enterprise Linux AI (RHEL AI) 3, Red Hat OpenShift AI (RHOAI) · no fix planned: Red Hat AI Inference Server, Red Hat Enterprise Linux AI (RHEL AI) 3, Red Hat OpenShift AI (RHOAI) · updated 2026-10-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-71486.json)