CVE intelligence

CVE-2026-84304

Vulnerability intelligence

Published Sep 1, 2026Sources checked Sep 12, 2026

8.7HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2026-84304 and is rated High severity with a CVSS score of 8.7. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

CISA KEVNot listedBased on the latest collected catalog

EPSS0.4%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-84304?

gRPC-Go is the Go language implementation of gRPC. Prior to 1.83.1, internal/transport/transport.go stores each fragmented HTTP/2 DATA frame as a separate recvMsg in recvBuffer, so millions of one-byte frames can consume disproportionate heap memory even when payload bytes remain within connection and stream flow-control windows. An unauthenticated remote attacker can use concurrent multiplexed streams to exhaust process memory and cause a runtime panic or out-of-memory termination. Receive-buffer compaction is enabled by default and can be controlled temporarily with GRPC_GO_EXPERIMENTAL_ENABLE_RECEIVE_BUFFER_COMPACTION. This issue is fixed in version 1.83.1.