CVE-2026-100647

vLLM versions before 0.29.0 contain a denial-of-service vulnerability in the cache_salt parameter accepted on OpenAI-compatible and Anthropic API endpoints, which lacks maximum length validation and is processed on the single EngineCore scheduler thread. Unauthenticated attackers can send HTTP requests with multi-hundred-megabyte salt values that trigger expensive pickle serialization and SHA-256 hashing, stalling the scheduler thread and denying service to all concurrent requests.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/vllm-project/vllm/security/advisories/GHSA-wpww-v874-ph2p	Vendor Advisory
https://www.vulncheck.com/advisories/vllm-before-0.29.0-cpu-exhaustion-via-unbounded-cache-salt	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:vllm:vllm:*:*:*:*:*:*:*:*

History

06 Oct 2026, 19:46

Type	Values Removed	Values Added
CPE		cpe:2.3:a:vllm:vllm::::::::
References	~~() https://github.com/vllm-project/vllm/security/advisories/GHSA-wpww-v874-ph2p -~~	() https://github.com/vllm-project/vllm/security/advisories/GHSA-wpww-v874-ph2p - Vendor Advisory
References	~~() https://www.vulncheck.com/advisories/vllm-before-0.29.0-cpu-exhaustion-via-unbounded-cache-salt -~~	() https://www.vulncheck.com/advisories/vllm-before-0.29.0-cpu-exhaustion-via-unbounded-cache-salt - Third Party Advisory
First Time		Vllm vllm Vllm

26 Sep 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-26 14:16

Updated : 2026-10-06 19:46

NVD link : CVE-2026-100647

Mitre link : CVE-2026-100647

CVE.ORG link : CVE-2026-100647

JSON object : View

Products Affected

vllm

vllm

CWE

CWE-20

Improper Input Validation

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