CVE-2026-47863

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{"bugzilla": {"description": "io.projectreactor/reactor-core: Reactor Core: Denial of Service in bufferTimeout operator", "id": "2524775", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2524775"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.9", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-770", "details": ["In Reactor Core, applications that use the Flux.bufferTimeout operator with fairBackpressure enabled are vulnerable to a Denial of Service (DoS) condition.\nReactor Core 3.8.0 - 3.8.6\nReactor Core 3.7.19 and earlier", "A flaw was found in Reactor Core. Applications using the `Flux.bufferTimeout` operator with `fairBackpressure` enabled are vulnerable to a Denial of Service (DoS) condition. This occurs when upstream components deliver items during an active flush, causing the processing pipeline to permanently hang and making the application unresponsive."], "mitigation": {"lang": "en:us", "value": "To mitigate this issue, applications should avoid using the `Flux.bufferTimeout` operator with `fairBackpressure` enabled. Review application code for instances where `fairBackpressure` is explicitly enabled with `Flux.bufferTimeout` and consider alternative buffering strategies or disabling `fairBackpressure` if it is not strictly required for the application's functionality."}, "name": "CVE-2026-47863", "package_state": [{"cpe": "cpe:/a:redhat:exploit_intelligence:0", "fix_state": "Out of support scope", "package_name": "exploit-intelligence/agent-client-rhel9", "product_name": "Exploit Intelligence"}, {"cpe": "cpe:/a:redhat:camel_quarkus:3", "fix_state": "Fix deferred", "package_name": "reactor-core", "product_name": "Red Hat build of Apache Camel 4 for Quarkus 3"}, {"cpe": "cpe:/a:redhat:debezium:3", "fix_state": "Fix deferred", "package_name": "reactor-core", "product_name": "Red Hat build of Debezium 3"}, {"cpe": "cpe:/a:redhat:quarkus:3", "fix_state": "Affected", "package_name": "reactor-core", "product_name": "Red Hat build of Quarkus"}, {"cpe": "cpe:/a:redhat:jboss_data_grid:8", "fix_state": "Fix deferred", "package_name": "reactor-core", "product_name": "Red Hat Data Grid 8"}, {"cpe": "cpe:/a:redhat:jboss_fuse:7", "fix_state": "Out of support scope", "package_name": "reactor-core", "product_name": "Red Hat Fuse 7"}], "public_date": "2026-08-26T23:28:48Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-47863\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-47863\nhttps://spring.io/security/cve-2026-47863"], "statement": "Moderate: Applications using the `Flux.bufferTimeout` operator with `fairBackpressure` enabled in Reactor Core are vulnerable to a Denial of Service condition. This impact is considered Moderate because exploitation requires a specific, non-default application configuration or usage pattern.", "threat_severity": "Moderate"}

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