CVE-2026-47857

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Source
https://cve.org/CVERecord?id=CVE-2026-47857
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-47857.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-47857
Downstream
CLSA (24)
Published
2026-08-26T23:28:44Z
Modified
2026-10-20T12:00:50Z
Severity
  • 5.9 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
Reactor Core windowTimeout fair-backpressure stream hang due to 20-bit index wrap-around
Details

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

Database specific 
{
    "cna_assigner":  "vmware",
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/47xxx/CVE-2026-47857.json",
    "unresolved_ranges":  [
        {
            "extracted_events":  [
                {
                    "introduced":  "3.8.0"
                },
                {
                    "last_affected":  "3.8.6"
                },
                {
                    "introduced":  "3.5.0"
                },
                {
                    "last_affected":  "3.7.19"
                },
                {
                    "last_affected":  "3.4.41"
                }
            ],
            "source":  "AFFECTED_FIELD"
        }
    ]
}
References

Affected packages

Git / github.com/reactor/reactor-core

Affected ranges

Type
GIT
Repo
https://github.com/reactor/reactor-core
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Last Affected
52d74fa45358f480e99a5f71d4192fc024bdb67d
Database specific
Show details 
{
    "extracted_events":  [
        {
            "range":  [
                {
                    "introduced":  "0"
                },
                {
                    "last_affected":  "3.4.41"
                }
            ],
            "source":  "DESCRIPTION"
        }
    ]
}

Affected versions

v2.*
v2.5.0.M1
v2.5.0.M2
v2.5.0.M3
v2.5.0.M4
v3.*
v3.0.0.RC1
v3.0.0.RC2
v3.0.0.RELEASE
v3.0.1.RELEASE
v3.0.2.RELEASE
v3.0.3.RELEASE
v3.0.4.RELEASE
v3.0.5.RELEASE
v3.0.6.RELEASE
v3.1.0.M1
v3.1.0.M2
v3.1.0.RELEASE
v3.1.1.RELEASE
v3.1.2.RELEASE
v3.1.3.RELEASE
v3.1.4.RELEASE
v3.2.0.M2
v3.2.0.M3
v3.2.0.M4
v3.2.0.RC1
v3.2.0.RELEASE
v3.2.1.RELEASE
v3.2.2.RELEASE
v3.2.3.RELEASE
v3.2.4.RELEASE
v3.2.5.RELEASE
v3.2.6.RELEASE
v3.3.0.M1
v3.3.0.M2
v3.3.0.M3
v3.3.0.RC1
v3.3.0.RELEASE
v3.3.1.RELEASE
v3.3.2.RELEASE
v3.3.3.RELEASE
v3.3.4.RELEASE
v3.3.5.RELEASE
v3.4.0
v3.4.0-M1
v3.4.0-M2
v3.4.0-RC1
v3.4.0-RC2
v3.4.1
v3.4.10
v3.4.11
v3.4.12
v3.4.13
v3.4.14
v3.4.15
v3.4.16
v3.4.17
v3.4.18
v3.4.19
v3.4.2
v3.4.20
v3.4.21
v3.4.22
v3.4.23
v3.4.24
v3.4.25
v3.4.26
v3.4.27
v3.4.28
v3.4.29
v3.4.3
v3.4.30
v3.4.31
v3.4.32
v3.4.33
v3.4.34
v3.4.35
v3.4.36
v3.4.37
v3.4.38
v3.4.39
v3.4.4
v3.4.40
v3.4.41
v3.4.5
v3.4.6
v3.4.7
v3.4.8
v3.4.9

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-47857.json"