Race Condition in vllm Project VLLM by vllm-project
CVE-2026-129356

2.3LOW

Key Information:

Vendor

Vllm-project

Status
Vllm
Vendor
CVE Published:
15 November 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-129356?

A vulnerability exists in the vllm-project's vllm versions 0.30.0 and 0.31.0 due to a race condition in the single_type_kv_cache_manager.py file. This flaw allows an attacker to exploit the manipulation of the Common Prefix Handler, potentially leading to unauthorized data access. The exploitation is complex and has been made public, emphasizing the urgent need for users to upgrade to version 0.32.0, which includes a patch to resolve this issue. Details about the patch can be found in the corresponding GitHub releases.

Affected Version(s)

vllm 0.30.0

vllm 0.31.0

vllm 0.32.0

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-129356 - Proof of Concept

References

https://vuldb.com/vuln/437419
vdb-entry
https://vuldb.com/vuln/437419/cti
signaturepermissions-required
https://vuldb.com/cve/CVE-2026-129356
third-party-advisory

CVSS V4

Score:
2.3
Severity:
LOW
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
High
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Zyz3366 (VulDB User)
.