CVE-2026-53321

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{"bugzilla": {"description": "kernel: io_uring/napi: cap busy_poll_to 10 msec", "id": "2493708", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2493708"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-835", "details": ["A flaw was found in the Linux kernel's io_uring subsystem, specifically in the Networked Asynchronous Packet Interface (NAPI) busy polling. This vulnerability allows NAPI to poll indefinitely for events when none are present, which can cause a task to become stuck. This can lead to a Denial of Service (DoS) condition, making the system unresponsive. The issue is addressed by implementing a 10-millisecond cap on the busy polling duration."], "name": "CVE-2026-53321", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-06-26T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-53321\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-53321\nhttps://lore.kernel.org/linux-cve-announce/2026062622-CVE-2026-53321-d475@gregkh/T"], "threat_severity": "Moderate"}

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