CVE-2026-47863 (GCVE-0-2026-47863)
Vulnerability from cvelistv5 – Published: 2026-08-26 23:28 – Updated: 2026-08-27 14:45
VLAI
EPSS
VEX
Title
Reactor Core bufferTimeout fair-backpressure pipeline permanently hangs when upstream delivers items during an active flush
Summary
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
Severity
5.9 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-27 14:45 UTC
CWE
- CWE-835 Loop with Unreachable Exit Condition ('Infinite Loop')
- CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
Assigner
References
1 reference
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Spring | Reactor Core |
Affected:
3.8.0 , ≤ 3.8.6
(custom)
Affected: 0 , ≤ 3.7.19 (custom) |
guessed |
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Sightings
| Author | Source | Type | Date | Other |
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Nomenclature
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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