CVE-2021-47123

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{"bugzilla": {"description": "kernel: io_uring: fix ltout double free on completion race", "id": "2269843", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2269843"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.1", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H", "status": "draft"}, "cwe": "CWE-415", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nio_uring: fix ltout double free on completion race\nAlways remove linked timeout on io_link_timeout_fn() from the master\nrequest link list, otherwise we may get use-after-free when first\nio_link_timeout_fn() puts linked timeout in the fail path, and then\nwill be found and put on master's free.", "A vulnerability was found in io_uring component of the Linux Kernel, where a double free error found due to a race condition in io_link_timeout_fn(). This occurred when a linked timeout was not properly removed from the master request list, leading to potential use-after-free issues and DoS."], "mitigation": {"lang": "en:us", "value": "Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update the affected package as soon as possible."}, "name": "CVE-2021-47123", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "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": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2024-03-15T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2021-47123\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-47123\nhttps://lore.kernel.org/linux-cve-announce/2024031511-CVE-2021-47123-8318@gregkh/T/#u"], "threat_severity": "Moderate"}

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