{"id":"CVE-2026-47857","state":"PUBLISHED","title":"Reactor Core windowTimeout fair-backpressure stream hang due to 20-bit index wrap-around","description":"In Reactor Core, applications that use the Flux.windowTimeout operator with fairBackpressure enabled are vulnerable to a Denial of Service (DoS) condition.\nReactor Core 3.8.0 - 3.8.6\nReactor Core 3.5.0 - 3.7.19\nReactor Core 3.4.41 and earlier","publishedAt":"2026-08-26T23:28:44.743Z","updatedAt":"2026-08-27T15:07:38.775Z","severity":{"score":5.9,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"vmware"},"assigner":"vmware","products":["Spring Reactor Core"],"affected":[{"vendor":"Spring","product":"Reactor Core","defaultStatus":"unaffected","versions":[{"version":"3.8.0","status":"affected","lessThanOrEqual":"3.8.6","versionType":"custom"},{"version":"3.5.0","status":"affected","lessThanOrEqual":"3.7.19","versionType":"custom"},{"version":"0","status":"affected","lessThanOrEqual":"3.4.41","versionType":"custom"}]}],"references":["https://spring.io/security/cve-2026-47857"],"weaknesses":["CWE-190"],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/47xxx/CVE-2026-47857.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-47857","state":"PUBLISHED","datePublished":"2026-08-26T23:28:44.743Z","dateUpdated":"2026-08-27T15:07:38.775Z","assignerShortName":"vmware","assignerOrgId":"dcf2e128-44bd-42ed-91e8-88f912c1401d","dateReserved":"2026-05-20T10:00:55.156Z"},"containers":{"cna":{"title":"Reactor Core windowTimeout fair-backpressure stream hang due to 20-bit index wrap-around","descriptions":[{"lang":"en","value":"In Reactor Core, applications that use the Flux.windowTimeout operator with fairBackpressure enabled are vulnerable to a Denial of Service (DoS) condition.\nReactor Core 3.8.0 - 3.8.6\nReactor Core 3.5.0 - 3.7.19\nReactor Core 3.4.41 and earlier"}],"affected":[{"vendor":"Spring","product":"Reactor Core","defaultStatus":"unaffected","versions":[{"version":"3.8.0","status":"affected","lessThanOrEqual":"3.8.6","versionType":"custom"},{"version":"3.5.0","status":"affected","lessThanOrEqual":"3.7.19","versionType":"custom"},{"version":"0","status":"affected","lessThanOrEqual":"3.4.41","versionType":"custom"}]}],"references":[{"url":"https://spring.io/security/cve-2026-47857"}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":5.9,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}}],"problemTypes":[{"descriptions":[{"lang":"en","description":"CWE-190 Integer Overflow or Wraparound","type":"CWE"}]}],"providerMetadata":{"shortName":"vmware","orgId":"dcf2e128-44bd-42ed-91e8-88f912c1401d","dateUpdated":"2026-08-26T23:28:44.743Z"},"impacts":[{"descriptions":[{"lang":"en","value":"In Reactor Core, applications that use the Flux.windowTimeout operator with fairBackpressure enabled are vulnerable to a Denial of Service (DoS) condition."}]}],"source":{"discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-27T15:07:04.132397Z","id":"CVE-2026-47857","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-190","type":"CWE","lang":"en","description":"CWE-190 Integer Overflow or Wraparound"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-27T15:07:38.775Z"}}]}}}