CVE-2026-84304
Unauthenticated remote memory exhaustion in grpc-go via many tiny HTTP/2 DATA frames.
Is CVE-2026-84304 being exploited?
Not confirmed. CVE-2026-84304 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.41% probability of exploitation in the next 30 days.
How severe is CVE-2026-84304?
CVE-2026-84304 is rated High with a CVSS score of 8.7. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-84304?
Yes. A fix has been recorded for CVE-2026-84304. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-84304 affect?
CVE-2026-84304 affects grpc-go <1.83.1, Go gRPC servers using HTTP/2, Microservices/cloud services built on grpc-go. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-84304?
Upgrade to grpc-go v1.83.1; temporarily disable receive-buffer compaction via env var if needed.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote unauthenticated attackers can exhaust process memory via concurrent multiplexed tiny HTTP/2 DATA frames, causing OOM, runtime panic, and service DoS.
Immediate action required
- affected< 1.83.1
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.