CVE-2026-47857 (GCVE-0-2026-47857)

Vulnerability from cvelistv5 – Published: 2026-08-26 23:28 – Updated: 2026-08-26 23:28
VLAI
Title
Reactor Core windowTimeout fair-backpressure stream hang due to 20-bit index wrap-around
Summary
In Reactor Core, applications that use the Flux.windowTimeout operator with fairBackpressure enabled are vulnerable to a Denial of Service (DoS) condition. Reactor Core 3.8.0 - 3.8.6 Reactor Core 3.5.0 - 3.7.19 Reactor Core 3.4.41 and earlier
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
Spring Reactor Core Affected: 3.8.0 , ≤ 3.8.6 (custom)
Affected: 3.5.0 , ≤ 3.7.19 (custom)
Affected: 0 , ≤ 3.4.41 (custom)
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.