{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-97938", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:18:58.204Z", "datePublished": "2026-09-25T10:22:51.720Z", "dateUpdated": "2026-10-21T12:53:45.385Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-21T12:53:45.385Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nreboot: fix cad_pid use-after-free race\n\ncad_pid is a single kernel-wide struct pid pointer. proc_do_cad_pid()\nreads it and passes it to pid_vnr() without protecting the lifetime of\nthe referenced struct pid. A concurrent writer can replace cad_pid and\ndrop the final reference to the old struct pid after the reader has\nloaded the pointer but before pid_vnr() has finished dereferencing it,\ncausing a use-after-free.\n\nkill_cad_pid() has the same lifetime race when it passes cad_pid to\nkill_pid().\n\nAt the time this issue was reported, an unprivileged user could reach the\nsysctl through user and PID namespaces because cad_pid was registered in\npid_table[]. Moving cad_pid back to the global reboot sysctl table\ncorrected that namespace and permission mismatch, but did not fix the\nunderlying lifetime race.\n\nFix this by treating cad_pid as an RCU-protected pointer at both read\nsites and by waiting for a grace period before dropping the old reference\non the write side.\n\ncall_rcu(&old_pid->rcu, ...) cannot be used here because free_pid()\nalso queues pid->rcu; queueing the same rcu_head twice can corrupt the\nRCU callback list.\n\nOriginal KASAN crash stack:\n kernel/pid.c:545 pid_nr_ns() # reads freed pid->level\n kernel/pid.c:556 pid_vnr() # calls pid_nr_ns()\n kernel/pid.c:775 proc_do_cad_pid() # calls pid_vnr(cad_pid)"}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["include/linux/sched.h", "include/linux/sched/signal.h", "init/main.c", "kernel/reboot.c", "kernel/signal.c"], "versions": [{"version": "9ec52099e4b8678a60e9f93e41ad87885d64f3e6", "lessThan": "0c1a966bc047af2801a70b8eb13f9df5d7ab925f", "status": "affected", "versionType": "git"}, {"version": "9ec52099e4b8678a60e9f93e41ad87885d64f3e6", "lessThan": "ae3e53fe3c1241855e3a88f74877738349948c78", "status": "affected", "versionType": "git"}, {"version": "9ec52099e4b8678a60e9f93e41ad87885d64f3e6", "lessThan": "ad72e2566643fff7f01666d845fb026898155e1f", "status": "affected", "versionType": "git"}, {"version": "9ec52099e4b8678a60e9f93e41ad87885d64f3e6", "lessThan": "9a17b0e053197a6a42cdc75e75a35b17aa662088", "status": "affected", "versionType": "git"}, {"version": "9ec52099e4b8678a60e9f93e41ad87885d64f3e6", "lessThan": "5a88f78df753993469dab4d1831f8fb4256a9468", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["include/linux/sched.h", "include/linux/sched/signal.h", "init/main.c", "kernel/reboot.c", "kernel/signal.c"], "versions": [{"version": "2.6.19", "status": "affected"}, {"version": "0", "lessThan": "2.6.19", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.112", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.53", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.7", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3", "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": "2.6.19", "versionEndExcluding": "6.6.160"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.19", "versionEndExcluding": "6.12.112"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.19", "versionEndExcluding": "6.18.53"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.19", "versionEndExcluding": "7.2.7"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.19", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/0c1a966bc047af2801a70b8eb13f9df5d7ab925f"}, {"url": "https://git.kernel.org/stable/c/ae3e53fe3c1241855e3a88f74877738349948c78"}, {"url": "https://git.kernel.org/stable/c/ad72e2566643fff7f01666d845fb026898155e1f"}, {"url": "https://git.kernel.org/stable/c/9a17b0e053197a6a42cdc75e75a35b17aa662088"}, {"url": "https://git.kernel.org/stable/c/5a88f78df753993469dab4d1831f8fb4256a9468"}], "title": "reboot: fix cad_pid use-after-free race", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["include/linux/sched.h", "include/linux/sched/signal.h", "init/main.c", "kernel/reboot.c", "kernel/signal.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "0c1a966bc047af2801a70b8eb13f9df5d7ab925f", "status": "affected", "version": "9ec52099e4b8678a60e9f93e41ad87885d64f3e6", "versionType": "git"}, {"lessThan": "ae3e53fe3c1241855e3a88f74877738349948c78", "status": "affected", "version": "9ec52099e4b8678a60e9f93e41ad87885d64f3e6", "versionType": "git"}, {"lessThan": "ad72e2566643fff7f01666d845fb026898155e1f", "status": "affected", "version": "9ec52099e4b8678a60e9f93e41ad87885d64f3e6", "versionType": "git"}, {"lessThan": "9a17b0e053197a6a42cdc75e75a35b17aa662088", "status": "affected", "version": "9ec52099e4b8678a60e9f93e41ad87885d64f3e6", "versionType": "git"}, {"lessThan": "5a88f78df753993469dab4d1831f8fb4256a9468", "status": "affected", "version": "9ec52099e4b8678a60e9f93e41ad87885d64f3e6", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["include/linux/sched.h", "include/linux/sched/signal.h", "init/main.c", "kernel/reboot.c", "kernel/signal.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "2.6.19"}, {"lessThan": "2.6.19", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.160", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.112", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.53", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.7", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "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\nreboot: fix cad_pid use-after-free race\n\ncad_pid is a single kernel-wide struct pid pointer. proc_do_cad_pid()\nreads it and passes it to pid_vnr() without protecting the lifetime of\nthe referenced struct pid. A concurrent writer can replace cad_pid and\ndrop the final reference to the old struct pid after the reader has\nloaded the pointer but before pid_vnr() has finished dereferencing it,\ncausing a use-after-free.\n\nkill_cad_pid() has the same lifetime race when it passes cad_pid to\nkill_pid().\n\nAt the time this issue was reported, an unprivileged user could reach the\nsysctl through user and PID namespaces because cad_pid was registered in\npid_table[]. Moving cad_pid back to the global reboot sysctl table\ncorrected that namespace and permission mismatch, but did not fix the\nunderlying lifetime race.\n\nFix this by treating cad_pid as an RCU-protected pointer at both read\nsites and by waiting for a grace period before dropping the old reference\non the write side.\n\ncall_rcu(&old_pid->rcu, ...) cannot be used here because free_pid()\nalso queues pid->rcu; queueing the same rcu_head twice can corrupt the\nRCU callback list.\n\nOriginal KASAN crash stack:\n kernel/pid.c:545 pid_nr_ns() # reads freed pid->level\n kernel/pid.c:556 pid_vnr() # calls pid_nr_ns()\n kernel/pid.c:775 proc_do_cad_pid() # calls pid_vnr(cad_pid)"}], "id": "CVE-2026-97938", "lastModified": "2026-10-21T13:21:16.970", "metrics": {}, "published": "2026-09-25T11:17:21.193", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/0c1a966bc047af2801a70b8eb13f9df5d7ab925f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/5a88f78df753993469dab4d1831f8fb4256a9468"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/9a17b0e053197a6a42cdc75e75a35b17aa662088"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/ad72e2566643fff7f01666d845fb026898155e1f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/ae3e53fe3c1241855e3a88f74877738349948c78"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: reboot: fix cad_pid use-after-free race", "id": "2541188", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2541188"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-825", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nreboot: fix cad_pid use-after-free race\ncad_pid is a single kernel-wide struct pid pointer. proc_do_cad_pid()\nreads it and passes it to pid_vnr() without protecting the lifetime of\nthe referenced struct pid. A concurrent writer can replace cad_pid and\ndrop the final reference to the old struct pid after the reader has\nloaded the pointer but before pid_vnr() has finished dereferencing it,\ncausing a use-after-free.\nkill_cad_pid() has the same lifetime race when it passes cad_pid to\nkill_pid().\nAt the time this issue was reported, an unprivileged user could reach the\nsysctl through user and PID namespaces because cad_pid was registered in\npid_table[]. Moving cad_pid back to the global reboot sysctl table\ncorrected that namespace and permission mismatch, but did not fix the\nunderlying lifetime race.\nFix this by treating cad_pid as an RCU-protected pointer at both read\nsites and by waiting for a grace period before dropping the old reference\non the write side.\ncall_rcu(&old_pid->rcu, ...) cannot be used here because free_pid()\nalso queues pid->rcu; queueing the same rcu_head twice can corrupt the\nRCU callback list.\nOriginal KASAN crash stack:\nkernel/pid.c:545 pid_nr_ns() # reads freed pid->level\nkernel/pid.c:556 pid_vnr() # calls pid_nr_ns()\nkernel/pid.c:775 proc_do_cad_pid() # calls pid_vnr(cad_pid)", "A flaw was found in the Linux kernel. A race condition in the reboot management subsystem allows a process identifier reference to be released while still being accessed by concurrent operations. A local attacker could exploit this use-after-free flaw to cause a Denial of Service (DoS) via a system crash or potentially escalate privileges."], "name": "CVE-2026-97938", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"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": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Affected", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Affected", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-09-25T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-97938\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-97938\nhttps://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-97938.mbox"], "threat_severity": "Moderate"}