CVE-2026-47863

MEDIUMPre-NVD 5.95.9—
EchelonGraph scoreHIGH confidence

Score 5.9 from GitHub Security Advisory published 2026-08-27. a secondary CVSS source baseline 5.9; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
5.9EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.9Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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

CVSS v3
5.9
EG Score
5.9(high)
EG Risk
27(Track)
EG Risk 27/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity59% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
13%
KEV
Not listed

Published

August 26, 2026

Last Modified

August 28, 2026

Advisory Details (1)

Auto-updated Aug 27, 2026
No patch confirmed yet.
generic

Reactor Core bufferTimeout fair-backpressure pipeline permanently hangs when upstream delivers items during an active flush

https://spring.io/security/cve-2026-47863

Vendor Advisories for CVE-2026-47863(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 14× in last 7d / 14× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-30 01:22 UTCEPSS rescore
  2. 2026-08-29 17:51 UTCEG score recompute
  3. 2026-08-29 17:51 UTCGHSA enrichment
  4. 2026-08-28 21:41 UTCEPSS rescore
  5. 2026-08-28 19:06 UTCGHSA enrichment
  6. 2026-08-28 16:22 UTCGHSA enrichment
  7. 2026-08-27 17:29 UTCEG score recompute
  8. 2026-08-27 17:29 UTCGHSA enrichment
  9. 2026-08-27 17:04 UTCEG score recompute
  10. 2026-08-27 17:04 UTCGHSA enrichment
  11. 2026-08-27 14:25 UTCEPSS rescore
  12. 2026-08-27 01:22 UTCEG score recompute
  13. 2026-08-27 00:22 UTCEG score recompute
  14. 2026-08-27 00:22 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-47863?
CVE-2026-47863 is a medium vulnerability published on August 26, 2026. 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
When was CVE-2026-47863 disclosed?
CVE-2026-47863 was first published in the National Vulnerability Database on August 26, 2026, with the most recent update on August 28, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-47863 actively exploited?
CVE-2026-47863 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 87.4% of all scored CVEs.
What is the CVSS score of CVE-2026-47863?
CVE-2026-47863 has a CVSS v3 base score of 5.9 (NVD).
How do I remediate CVE-2026-47863?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-47863, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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