CVE-2026-34756
Estado: ModificadaMedia (6.5)—
vLLM is an inference and serving engine for large language models (LLMs). From 0.1.0 to before 0.19.0, a Denial of Service vulnerability exists in the vLLM OpenAI-compatible API server. Due to the lack of an upper bound validation on the n parameter in the ChatCompletionRequest and CompletionRequest Pydantic models, an unauthenticated attacker can send a single HTTP request with an astronomically large n value. This completely blocks the Python asyncio event loop and causes immediate Out-Of-Memory crashes by allocating millions of request object copies in the heap before the request even reaches the scheduling queue. This vulnerability is fixed in 0.19.0.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 6.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.77%
- Percentil entre todas las CVEs puntuadas: 54
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
CWE
- CWE-770
- CWE-1284
Referencias
- https://github.com/vllm-project/vllm/commit/b111f8a61f100fdca08706f41f29ef3548de7380
- https://github.com/vllm-project/vllm/pull/37952
- https://github.com/vllm-project/vllm/security/advisories/GHSA-3mwp-wvh9-7528
- https://access.redhat.com/errata/RHSA-2026:36005
- https://access.redhat.com/errata/RHSA-2026:36006
- https://access.redhat.com/errata/RHSA-2026:57380
- https://access.redhat.com/errata/RHSA-2026:57387
- https://access.redhat.com/errata/RHSA-2026:57389
- https://access.redhat.com/errata/RHSA-2026:57390
- https://access.redhat.com/errata/RHSA-2026:59144
- https://access.redhat.com/errata/RHSA-2026:59151
- https://access.redhat.com/security/cve/CVE-2026-34756
- https://bugzilla.redhat.com/show_bug.cgi?id=2455425
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-34756.json
JSON original (NVD)
Mostrar
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