CVE-2026-84304
Fix: grpc/grpc-go@7354d9cCVE-2026-84304 is a Uncontrolled Resource Consumption vulnerability. O3 Security confirms whether CVE-2026-84304 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
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…
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-84304.
Description
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.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for CVE-2026-84304 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-84304 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-84304. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-84304 in your dependencies?
O3 detects CVE-2026-84304 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.