Reference page — cumulative record through Sunday, October 4, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
CVE-2026-47863
Spring Reactor Core — Reactor Core bufferTimeout fair-backpressure pipeline permanently hangs when upstream delivers items during an active flush
AV AC PR UI S C I A CVSS EPSS %ile KEV
N L N N U N N H 7.5 .0040 32.4 —
AFFECTED
Product Versions Fixed
Reactor Core 3.8.0 – —
TIMELINE
May 20 Reserved by vmware
Aug 26 Published (CNA: vmware)
Sep 1 RESCORED — CVE-2026-47863 (Spring Reactor Core). CVSS 5.9 → 7.5 (NVD).
Description
In Reactor Core, applications that use the Flux.bufferTimeout operator with fairBackpressure enabled are vulnerable to a Denial of Service (DoS) condition.
Reactor Core 3.8.0 - 3.8.6
Reactor Core 3.7.19 and earlier
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
|---|
| May 20, 2026 | Reserved | Reserved by vmware |
| August 26, 2026 | Published | Published (CNA: vmware) |
| September 1, 2026 | RESCORED | RESCORED — CVE-2026-47863 (Spring Reactor Core). CVSS 5.9 → 7.5 (NVD). |
Affected
Affected products and packages — 1 row
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|
| Spring | Reactor Core | — | 3.8.0 | — |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-47863 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Sunday, October 4, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.
