Deserialization of Untrusted Data Affecting vllm package, versions [,0.32.0)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published27 Oct 2026
- disclosed26 Oct 2026
- creditClinton Thomas
Introduced: 26 Oct 2026
NewCVE-2026-115912 (opens in a new tab)How to fix?
Upgrade vllm to version 0.32.0 or higher.
Overview
vllm is an A high-throughput and memory-efficient inference and serving engine for LLMs
Affected versions of this package are vulnerable to Deserialization of Untrusted Data in the shared-memory multimodal cache handle mechanism, where handles passed between processes via SingleWriterShmRingBuffer are not authenticated. An attacker with local access can forge or tamper with shared-memory handles to cause a process to read from an arbitrary memory region, achieving unauthorized access to cached multimodal data or corrupting inference state. The fix introduces a 32-byte HMAC signing secret stored in the shared-memory segment itself, so that all handles are cryptographically verified before use.
Details
Serialization is a process of converting an object into a sequence of bytes which can be persisted to a disk or database or can be sent through streams. The reverse process of creating object from sequence of bytes is called deserialization. Serialization is commonly used for communication (sharing objects between multiple hosts) and persistence (store the object state in a file or a database). It is an integral part of popular protocols like Remote Method Invocation (RMI), Java Management Extension (JMX), Java Messaging System (JMS), Action Message Format (AMF), Java Server Faces (JSF) ViewState, etc.
Deserialization of untrusted data (CWE-502) is when the application deserializes untrusted data without sufficiently verifying that the resulting data will be valid, thus allowing the attacker to control the state or the flow of the execution.