Skip to main content

vLLM EUVDEUVD-2026-83617

| CVE-2026-93989 LOW
Improper Validation of Array Index (CWE-129)
2026-09-19 VulnCheck GHSA-pc5q-2x89-w436
2.3
CVSS 4.0 · Vendor: VulnCheck

Severity by source

Vendor (VulnCheck) PRIMARY
2.3 LOW
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
vuln.today AI
3.1 LOW

Reachable via inference API (AV:N) but needs a specific multimodal model mismatch plus concurrency (AC:H) and request-submission access (PR:L); impact is integrity-only corruption of outputs (I:L), no disclosure or DoS.

3.1 AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
4.0 AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

Primary rating from Vendor (VulnCheck).

CVSS VectorVendor: VulnCheck

Attack Vector
Network
Attack Complexity
High
Privileges Required
Low
User Interaction
None
Scope
X

Lifecycle Timeline

1
Analysis Generated
Sep 19, 2026 - 23:34 vuln.today

DescriptionCVE.org

vLLM through 0.29.0 fails to properly validate bad_words token indices against the model's generation output width in SamplingParams.update_from_tokenizer(). Attackers can supply out-of-bounds token indices that corrupt logits memory of concurrent requests, causing different in-flight HTTP requests to return incorrect tokens.

AnalysisAI

Out-of-bounds bad_words token indices in vLLM through 0.29.0 are not validated against the model's generation output width, allowing the indices to be written past the logits buffer and corrupt the sampling state of concurrently batched requests, so unrelated in-flight HTTP requests can receive incorrect output tokens. Exploitation requires API access sufficient to submit sampling requests with a bad_words parameter (authenticated, PR:L), a target model whose tokenizer exposes input-only placeholder tokens with IDs above the model's logits vocabulary (typically multimodal models such as those with <|audio|> tokens), and concurrent requests sharing the batch, so a text-only model whose tokenizer vocabulary equals its output vocabulary is not affected. …

Unlock full vulnerability intelligence

  • Risk assessment & exploitation conditions
  • Attack chain visualization
  • Remediation with exact patch versions
  • Threat intelligence from 22 sources
  • Personal watchlist & email alerts

Free forever · No credit card required

Attack ChainAIDerived

Hypothetical attack flow derived from CVE metadata

Access
technique details hidden
Delivery
technique details hidden
Exploit
technique details hidden
Execution
technique details hidden
Persist
technique details hidden
Impact
technique details hidden

Vulnerability AssessmentAI

Exploitation Exploitation requires the ability to submit sampling requests (bad_words parameter) to a vLLM inference endpoint (through 0.29.0), and - per the fix's regression tests - a model whose tokenizer contains input-only placeholder tokens (e.g. … Additional conditions and limiting factors are described in the full assessment.
Risk Assessment All signals point to a genuinely LOW-priority issue despite the alarming-sounding 'cross-request corruption' description. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in.
Exploit Scenario Full exploit scenario with step-by-step reproduction available after sign-in.
Remediation Upstream fix available (PR/commit); released patched version not independently confirmed - the corrective change is in https://github.com/vllm-project/vllm/pull/48824, which validates bad_words IDs against model_config.get_vocab_size() (max valid ID = vocab_size - 1), passes the logits output_width into the BadWords path, and adds a bounds guard before applying a match, so upgrade to a vLLM build that contains this commit (anything released after 0.29.0, since 0.29.0 and earlier are affected) once a tagged release including it is verified. … Detailed patch versions, workarounds, and compensating controls in full report.

Threat intelligence, references, and detailed analysis are available after sign-in.

More in Vllm

View all
CVE-2025-32444 CRITICAL POC
10.0 Apr 30

vLLM is a high-throughput and memory-efficient inference and serving engine for LLMs. Rated critical severity (CVSS 10.0

CVE-2024-11041 CRITICAL POC
9.8 Mar 20

vllm-project vllm version v0.6.2 contains a vulnerability in the MessageQueue.dequeue() API function. Rated critical sev

CVE-2026-22778 CRITICAL POC
9.8 Feb 02

Information exposure in vLLM inference engine versions 0.8.3 to before 0.14.1. Invalid image requests to the multimodal

CVE-2025-30202 HIGH POC
7.5 Apr 30

vLLM is a high-throughput and memory-efficient inference and serving engine for LLMs. Rated high severity (CVSS 7.5), th

CVE-2026-24779 HIGH POC
7.1 Jan 27

vLLM before version 0.14.1 contains a server-side request forgery vulnerability in the MediaConnector class where incons

CVE-2025-46560 MEDIUM POC
6.5 Apr 30

vLLM is a high-throughput and memory-efficient inference and serving engine for LLMs. Rated medium severity (CVSS 6.5),

CVE-2026-73559 MEDIUM POC
6.5 Aug 13

Uncontrolled resource consumption in vLLM's OpenAI-compatible completions endpoint allows any authenticated API client t

CVE-2026-22773 MEDIUM POC
6.5 Jan 10

Vllm versions up to 0.12.0 is affected by allocation of resources without limits or throttling (CVSS 6.5).

CVE-2026-57173 MEDIUM POC
6.5 Sep 16

Out-of-memory worker crashes in vLLM can be induced by a single small compressed audio payload submitted to the /v1/chat

CVE-2026-73557 MEDIUM POC
6.3 Aug 13

Race condition in vLLM's prompt embedding loader allows concurrent API requests to bypass the sparse tensor invariant gu

CVE-2026-22807 CRITICAL
9.8 Jan 21

Remote code execution in vLLM 0.10.1 through 0.13.x lets an attacker who controls the model repository or path run arbit

CVE-2026-25960 CRITICAL
9.8 Mar 09

Server-Side Request Forgery in vLLM's multimodal MediaConnector allows remote attackers to coerce the inference server i

Share

EUVD-2026-83617 vulnerability details – vuln.today

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy