CVE-2026-47857: broadcom reactor_core Integer Overflow or Wraparound

Vulnerability summary

CVE-2026-47857 is a medium (CVSS 5.9) Integer Overflow or Wraparound vulnerability in broadcom reactor_core. EPSS estimates a 0.37% chance of exploitation in the next 30 days, higher than 28.9% of scored vulnerabilities.

Timeline

1. 26-08-2026
   PublishedVulnerability first disclosed.
2. 27-08-2026
   Last modifiedVulnerability information updated.

Description

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

• CWE-190Integer Overflow or WraparoundThe product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.