CVE-2026-99280

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-99280", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.405Z", "datePublished": "2026-11-07T14:08:47.488Z", "dateUpdated": "2026-11-07T14:08:47.488Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-11-07T14:08:47.488Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: drain session procfs readers before dropping table references\n\nSession registration failure and connection cleanup can drop the table\nreference while the per-session procfs entry is still accessible. If a\nreader holds the last remaining reference, its final put calls\nproc_remove() from its own callback and waits for that callback to\nfinish.\n\nRemove the procfs entry before dropping the table reference in the\nregistration failure path. Queue sessions removed during connection\ncleanup and drain their procfs readers after releasing both session\nlocks, then return their table references. Keep the global hash node\nunhashed while a session is queued so a concurrent unregister cannot\ndrop the reference again.\n\nPrevious-session replacement also destroys the file table before the\nsession is finally freed. Detach the idr under the lock used by procfs\nfile counters, and report zero files after it has been detached. This\nprevents a reader from accessing the idr during or after its\ndestruction."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/smb/server/mgmt/user_session.c", "fs/smb/server/vfs_cache.c"], "versions": [{"version": "d7fd1f98607f2cd358e583f9548bdf0173090a86", "lessThan": "6789f0983f8e85ce3a5ed8c50fc05d613ead9c2c", "status": "affected", "versionType": "git"}, {"version": "d7fd1f98607f2cd358e583f9548bdf0173090a86", "lessThan": "1c087cf7d5386c708d8984b263280b42b3daada0", "status": "affected", "versionType": "git"}, {"version": "c99ea7855124ca1428a1e59c2b4590aaef34eacf", "status": "affected", "versionType": "git"}, {"version": "7.2.8", "lessThan": "7.3", "status": "affected", "versionType": "semver"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/smb/server/mgmt/user_session.c", "fs/smb/server/vfs_cache.c"], "versions": [{"version": "7.3", "status": "affected"}, {"version": "0", "lessThan": "7.3", "status": "unaffected", "versionType": "semver"}, {"version": "7.3.2", "lessThanOrEqual": "7.3.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.4-rc1", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.3", "versionEndExcluding": "7.3.2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.3", "versionEndExcluding": "7.4-rc1"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.2.8"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/6789f0983f8e85ce3a5ed8c50fc05d613ead9c2c"}, {"url": "https://git.kernel.org/stable/c/1c087cf7d5386c708d8984b263280b42b3daada0"}], "title": "ksmbd: drain session procfs readers before dropping table references", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/smb/server/mgmt/user_session.c", "fs/smb/server/vfs_cache.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "6789f0983f8e85ce3a5ed8c50fc05d613ead9c2c", "status": "affected", "version": "d7fd1f98607f2cd358e583f9548bdf0173090a86", "versionType": "git"}, {"lessThan": "1c087cf7d5386c708d8984b263280b42b3daada0", "status": "affected", "version": "d7fd1f98607f2cd358e583f9548bdf0173090a86", "versionType": "git"}, {"status": "affected", "version": "c99ea7855124ca1428a1e59c2b4590aaef34eacf", "versionType": "git"}, {"lessThan": "7.3", "status": "affected", "version": "7.2.8", "versionType": "semver"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/smb/server/mgmt/user_session.c", "fs/smb/server/vfs_cache.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "7.3"}, {"lessThan": "7.3", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "7.3.*", "status": "unaffected", "version": "7.3.2", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.4-rc1", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: drain session procfs readers before dropping table references\n\nSession registration failure and connection cleanup can drop the table\nreference while the per-session procfs entry is still accessible. If a\nreader holds the last remaining reference, its final put calls\nproc_remove() from its own callback and waits for that callback to\nfinish.\n\nRemove the procfs entry before dropping the table reference in the\nregistration failure path. Queue sessions removed during connection\ncleanup and drain their procfs readers after releasing both session\nlocks, then return their table references. Keep the global hash node\nunhashed while a session is queued so a concurrent unregister cannot\ndrop the reference again.\n\nPrevious-session replacement also destroys the file table before the\nsession is finally freed. Detach the idr under the lock used by procfs\nfile counters, and report zero files after it has been detached. This\nprevents a reader from accessing the idr during or after its\ndestruction."}], "id": "CVE-2026-99280", "lastModified": "2026-11-07T14:17:03.453", "metrics": {}, "published": "2026-11-07T14:17:03.453", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/1c087cf7d5386c708d8984b263280b42b3daada0"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/6789f0983f8e85ce3a5ed8c50fc05d613ead9c2c"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: kernel: Denial of Service via improper session cleanup in ksmbd", "id": "2568639", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2568639"}, "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-833", "details": ["A flaw was found in the Linux kernel's ksmbd. Session registration failures and connection cleanups can drop internal session references while the per-session procfs (process information pseudo-filesystem) entry is still accessible. A local user reading these entries during concurrent session teardown can trigger a deadlock or memory corruption, resulting in a Denial of Service (DoS)."], "mitigation": {"lang": "en:us", "value": "To mitigate this vulnerability, prevent the ksmbd kernel module from being loaded:\n1. Create a configuration file to disable the module:\necho \"install ksmbd /bin/true\" > /etc/modprobe.d/ksmbd.conf\n2. If the module is already loaded, unload it:\nmodprobe -r ksmbd\nCaveat: Disabling this module prevents the system from running the in-kernel SMB server.\nWarning: If the module is currently in use, unloading it will disrupt active SMB connections. A system restart may be required if the module cannot be unloaded dynamically."}, "name": "CVE-2026-99280", "package_state": [{"cpe": "cpe:/a:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:rhel_els:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:rhel_els:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:rhel_els:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/a:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/a:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/a:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:5", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-10", "product_name": "Red Hat OpenShift Container Platform 5"}, {"cpe": "cpe:/a:redhat:openshift:5", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 5"}], "public_date": "2026-11-07T14:08:47Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-99280\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-99280\nhttps://git.kernel.org/stable/c/1c087cf7d5386c708d8984b263280b42b3daada0\nhttps://git.kernel.org/stable/c/6789f0983f8e85ce3a5ed8c50fc05d613ead9c2c"], "statement": "This vulnerability is rated as having Moderate severity for Red Hat because successful exploitation requires local authenticated access and results exclusively in a denial of service without impacting confidentiality or integrity. By default, Red Hat Enterprise Linux utilizes Samba as the supported userspace SMB solution and does not enable the in-kernel ksmbd server. Consequently, systems operating with default configurations are not exposed unless ksmbd has been explicitly loaded and configured.", "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[d7fd1f98607f2cd358e583f9548bdf0173090a86,6789f0983f8e85ce3a5ed8c50fc05d613ead9c2c)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[d7fd1f98607f2cd358e583f9548bdf0173090a86,1c087cf7d5386c708d8984b263280b42b3daada0)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "c99ea7855124ca1428a1e59c2b4590aaef34eacf"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[7.2.8,7.3)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "7.3"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,7.3)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.3.2,7.4.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.4-rc1,*]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[d7fd1f98607f2cd358e583f9548bdf0173090a86,6789f0983f8e85ce3a5ed8c50fc05d613ead9c2c)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[d7fd1f98607f2cd358e583f9548bdf0173090a86,1c087cf7d5386c708d8984b263280b42b3daada0)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "c99ea7855124ca1428a1e59c2b4590aaef34eacf"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[7.2.8,7.3)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "7.3"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,7.3)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.3.2,7.4.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.4-rc1,*]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-11-07T15:30:07.507104+00:00", "updated": "2026-11-08T03:30:15.789075+00:00", "vendors": ["linux", "linux$PRODUCT$linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-833"]}