CVE-2026-93989

vLLM through 0.29.0 Cross-Request Logits Corruption via bad_words

MEDIUM
4.3
CVSS Score
Published: September 19, 2026 at 10:58 PM UTC
Updated: September 28, 2026 at 06:38 PM UTC
1 product affected across 1 vendorvLLM

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Severity
MEDIUM4.3
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v ≤ 0.29.0

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-129

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