CVE-2026-114049

vLLM before 0.31.0 Stale allowed_token_ids Mask via InputBatch.condense

LOW
3.7
CVSS Score
Published: October 21, 2026 at 12:36 AM UTC
Updated: October 28, 2026 at 04:17 PM UTC
1 product affected across 1 vendorvLLM

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Severity
LOW3.7
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

Description

vLLM before 0.31.0 contains a cross-request mask leak in InputBatch.condense() that allows remote attackers to constrain other clients' outputs by leaving stale allowed_token_ids rows. Attackers can submit concurrent constrained generate requests, including via unauthenticated /invocations, so recycled batch slots apply their token allowlist to victims' unrestricted requests.

Affected

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

All versions
Vendor states this is fixed in 0.31.0 (unaffected)

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

3.7LOWVulnCheck
Attack Vector
NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusUNDERGOING ANALYSIS
CWE
CWE-440

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