{"api_version":"1","generated_at":"2026-08-15T16:26:27+00:00","cve":"CVE-2026-72183","urls":{"html":"https://cve.report/CVE-2026-72183","api":"https://cve.report/api/cve/CVE-2026-72183.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-72183","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-72183"},"summary":{"title":"landlock: Fix LANDLOCK_SCOPE_SIGNAL bypass on the SIGIO path","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nlandlock: Fix LANDLOCK_SCOPE_SIGNAL bypass on the SIGIO path\n\nLANDLOCK_SCOPE_SIGNAL must prevent a sandboxed process from signaling\nprocesses outside its Landlock domain.  It can be bypassed through the\nasynchronous SIGIO delivery path.\n\nA sandboxed process that owns any file or socket can arm it with\nfcntl(fd, F_SETOWN, -pgid), fcntl(fd, F_SETSIG, SIGKILL) and O_ASYNC, so\nthat an I/O event makes the kernel deliver the chosen signal to the\nwhole process group.  As the head of its process group's task list (the\ndefault position right after fork()) that group can also hold the\nnon-sandboxed process that launched it, e.g. a supervisor or a security\nmonitor.  The sandbox can thus kill or signal the processes\nLANDLOCK_SCOPE_SIGNAL is meant to protect from it.\n\nThe scope is enforced in hook_file_send_sigiotask() against the Landlock\ndomain recorded at F_SETOWN time, not the live domain of the sender.\ncontrol_current_fowner() decides whether to record that domain and skips\nrecording it when the fowner target is in the caller's thread group,\nwhich is safe only for a single-task target (PIDTYPE_PID, PIDTYPE_TGID).\nFor a process group (PIDTYPE_PGID) pid_task() returns only one member;\nrecording is skipped whenever that member shares the caller's thread\ngroup, and hook_file_send_sigiotask() then lets the signal fan out to\nthe whole group unchecked.\n\nRecord the domain for every non single-process target so the scope is\nenforced against each group member at delivery time.\n\nThat recording is necessary but not sufficient on its own: the kernel\nsignals a process group through its members' thread-group leaders, and\nthe leader of the registrant's own process can carry a different\nLandlock domain than the sibling thread that armed the owner.\ndomain_is_scoped() would then deny that leader, even though commit\n18eb75f3af40 (\"landlock: Always allow signals between threads of the\nsame process\") requires same-process delivery to be allowed.\nhook_task_kill() avoids this by evaluating same_thread_group() live, per\nrecipient; the SIGIO path instead delegates the whole decision to a\nsingle registration-time check, which a process-group fan-out cannot\nhonor.\n\nSo also record the registrant's thread group next to its domain and\nexempt it at delivery: hook_file_send_sigiotask() allows the signal\nwhenever the recipient belongs to the registrant's own process,\nrestoring the same-process guarantee while keeping out-of-domain group\nmembers blocked.  The direct kill() path (hook_task_kill) already\nevaluates the live domain and is unaffected.\n\n[mic: Check pid_type earlier and improve comment, fix commit message,\nfix comment formatting]","state":"PUBLISHED","assigner":"Linux","published_at":"2026-08-15 06:21:36","updated_at":"2026-08-15 06:21:36"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/7a92e9fd1d496a610b40e0c4253fd54e7496f5ab","name":"https://git.kernel.org/stable/c/7a92e9fd1d496a610b40e0c4253fd54e7496f5ab","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/1f18aac2637220b5847d073447498e81ddca10b2","name":"https://git.kernel.org/stable/c/1f18aac2637220b5847d073447498e81ddca10b2","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/04916f7dc6d37cd478b06c86398c34a6963ac8c9","name":"https://git.kernel.org/stable/c/04916f7dc6d37cd478b06c86398c34a6963ac8c9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/4b80320ca7ed03d6e683f95b6066565dc97b9f92","name":"https://git.kernel.org/stable/c/4b80320ca7ed03d6e683f95b6066565dc97b9f92","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-72183","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-72183","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 332facfa80751b80006c2f95b13c6d208ab0aee1 7a92e9fd1d496a610b40e0c4253fd54e7496f5ab git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 18eb75f3af40be1f0fc2025d4ff821711222a2fd 1f18aac2637220b5847d073447498e81ddca10b2 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 18eb75f3af40be1f0fc2025d4ff821711222a2fd 04916f7dc6d37cd478b06c86398c34a6963ac8c9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 18eb75f3af40be1f0fc2025d4ff821711222a2fd 4b80320ca7ed03d6e683f95b6066565dc97b9f92 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6861348d863c0eaa4af67492d640a9644a829c59 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 0906a9685d7057aea982e970da3e1cf3e5aca68b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.12.24 6.12.101 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.13.12 6.14 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.14.3 6.15 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.15","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.15 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.101 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.40 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.5 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["security/landlock/fs.c","security/landlock/fs.h","security/landlock/task.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"7a92e9fd1d496a610b40e0c4253fd54e7496f5ab","status":"affected","version":"332facfa80751b80006c2f95b13c6d208ab0aee1","versionType":"git"},{"lessThan":"1f18aac2637220b5847d073447498e81ddca10b2","status":"affected","version":"18eb75f3af40be1f0fc2025d4ff821711222a2fd","versionType":"git"},{"lessThan":"04916f7dc6d37cd478b06c86398c34a6963ac8c9","status":"affected","version":"18eb75f3af40be1f0fc2025d4ff821711222a2fd","versionType":"git"},{"lessThan":"4b80320ca7ed03d6e683f95b6066565dc97b9f92","status":"affected","version":"18eb75f3af40be1f0fc2025d4ff821711222a2fd","versionType":"git"},{"status":"affected","version":"6861348d863c0eaa4af67492d640a9644a829c59","versionType":"git"},{"status":"affected","version":"0906a9685d7057aea982e970da3e1cf3e5aca68b","versionType":"git"},{"lessThan":"6.12.101","status":"affected","version":"6.12.24","versionType":"semver"},{"lessThan":"6.14","status":"affected","version":"6.13.12","versionType":"semver"},{"lessThan":"6.15","status":"affected","version":"6.14.3","versionType":"semver"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["security/landlock/fs.c","security/landlock/fs.h","security/landlock/task.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.15"},{"lessThan":"6.15","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.101","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.40","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.5","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.101","versionStartIncluding":"6.12.24","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.40","versionStartIncluding":"6.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.5","versionStartIncluding":"6.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2-rc1","versionStartIncluding":"6.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.14.3","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nlandlock: Fix LANDLOCK_SCOPE_SIGNAL bypass on the SIGIO path\n\nLANDLOCK_SCOPE_SIGNAL must prevent a sandboxed process from signaling\nprocesses outside its Landlock domain.  It can be bypassed through the\nasynchronous SIGIO delivery path.\n\nA sandboxed process that owns any file or socket can arm it with\nfcntl(fd, F_SETOWN, -pgid), fcntl(fd, F_SETSIG, SIGKILL) and O_ASYNC, so\nthat an I/O event makes the kernel deliver the chosen signal to the\nwhole process group.  As the head of its process group's task list (the\ndefault position right after fork()) that group can also hold the\nnon-sandboxed process that launched it, e.g. a supervisor or a security\nmonitor.  The sandbox can thus kill or signal the processes\nLANDLOCK_SCOPE_SIGNAL is meant to protect from it.\n\nThe scope is enforced in hook_file_send_sigiotask() against the Landlock\ndomain recorded at F_SETOWN time, not the live domain of the sender.\ncontrol_current_fowner() decides whether to record that domain and skips\nrecording it when the fowner target is in the caller's thread group,\nwhich is safe only for a single-task target (PIDTYPE_PID, PIDTYPE_TGID).\nFor a process group (PIDTYPE_PGID) pid_task() returns only one member;\nrecording is skipped whenever that member shares the caller's thread\ngroup, and hook_file_send_sigiotask() then lets the signal fan out to\nthe whole group unchecked.\n\nRecord the domain for every non single-process target so the scope is\nenforced against each group member at delivery time.\n\nThat recording is necessary but not sufficient on its own: the kernel\nsignals a process group through its members' thread-group leaders, and\nthe leader of the registrant's own process can carry a different\nLandlock domain than the sibling thread that armed the owner.\ndomain_is_scoped() would then deny that leader, even though commit\n18eb75f3af40 (\"landlock: Always allow signals between threads of the\nsame process\") requires same-process delivery to be allowed.\nhook_task_kill() avoids this by evaluating same_thread_group() live, per\nrecipient; the SIGIO path instead delegates the whole decision to a\nsingle registration-time check, which a process-group fan-out cannot\nhonor.\n\nSo also record the registrant's thread group next to its domain and\nexempt it at delivery: hook_file_send_sigiotask() allows the signal\nwhenever the recipient belongs to the registrant's own process,\nrestoring the same-process guarantee while keeping out-of-domain group\nmembers blocked.  The direct kill() path (hook_task_kill) already\nevaluates the live domain and is unaffected.\n\n[mic: Check pid_type earlier and improve comment, fix commit message,\nfix comment formatting]"}],"providerMetadata":{"dateUpdated":"2026-08-15T05:53:45.922Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/7a92e9fd1d496a610b40e0c4253fd54e7496f5ab"},{"url":"https://git.kernel.org/stable/c/1f18aac2637220b5847d073447498e81ddca10b2"},{"url":"https://git.kernel.org/stable/c/04916f7dc6d37cd478b06c86398c34a6963ac8c9"},{"url":"https://git.kernel.org/stable/c/4b80320ca7ed03d6e683f95b6066565dc97b9f92"}],"title":"landlock: Fix LANDLOCK_SCOPE_SIGNAL bypass on the SIGIO path","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-72183","datePublished":"2026-08-15T05:53:45.922Z","dateReserved":"2026-08-09T03:40:39.910Z","dateUpdated":"2026-08-15T05:53:45.922Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-15 06:21:36","lastModifiedDate":"2026-08-15 06:21:36","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"72183","Ordinal":"1","Title":"landlock: Fix LANDLOCK_SCOPE_SIGNAL bypass on the SIGIO path","CVE":"CVE-2026-72183","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"72183","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nlandlock: Fix LANDLOCK_SCOPE_SIGNAL bypass on the SIGIO path\n\nLANDLOCK_SCOPE_SIGNAL must prevent a sandboxed process from signaling\nprocesses outside its Landlock domain.  It can be bypassed through the\nasynchronous SIGIO delivery path.\n\nA sandboxed process that owns any file or socket can arm it with\nfcntl(fd, F_SETOWN, -pgid), fcntl(fd, F_SETSIG, SIGKILL) and O_ASYNC, so\nthat an I/O event makes the kernel deliver the chosen signal to the\nwhole process group.  As the head of its process group's task list (the\ndefault position right after fork()) that group can also hold the\nnon-sandboxed process that launched it, e.g. a supervisor or a security\nmonitor.  The sandbox can thus kill or signal the processes\nLANDLOCK_SCOPE_SIGNAL is meant to protect from it.\n\nThe scope is enforced in hook_file_send_sigiotask() against the Landlock\ndomain recorded at F_SETOWN time, not the live domain of the sender.\ncontrol_current_fowner() decides whether to record that domain and skips\nrecording it when the fowner target is in the caller's thread group,\nwhich is safe only for a single-task target (PIDTYPE_PID, PIDTYPE_TGID).\nFor a process group (PIDTYPE_PGID) pid_task() returns only one member;\nrecording is skipped whenever that member shares the caller's thread\ngroup, and hook_file_send_sigiotask() then lets the signal fan out to\nthe whole group unchecked.\n\nRecord the domain for every non single-process target so the scope is\nenforced against each group member at delivery time.\n\nThat recording is necessary but not sufficient on its own: the kernel\nsignals a process group through its members' thread-group leaders, and\nthe leader of the registrant's own process can carry a different\nLandlock domain than the sibling thread that armed the owner.\ndomain_is_scoped() would then deny that leader, even though commit\n18eb75f3af40 (\"landlock: Always allow signals between threads of the\nsame process\") requires same-process delivery to be allowed.\nhook_task_kill() avoids this by evaluating same_thread_group() live, per\nrecipient; the SIGIO path instead delegates the whole decision to a\nsingle registration-time check, which a process-group fan-out cannot\nhonor.\n\nSo also record the registrant's thread group next to its domain and\nexempt it at delivery: hook_file_send_sigiotask() allows the signal\nwhenever the recipient belongs to the registrant's own process,\nrestoring the same-process guarantee while keeping out-of-domain group\nmembers blocked.  The direct kill() path (hook_task_kill) already\nevaluates the live domain and is unaffected.\n\n[mic: Check pid_type earlier and improve comment, fix commit message,\nfix comment formatting]","Type":"Description","Title":"landlock: Fix LANDLOCK_SCOPE_SIGNAL bypass on the SIGIO path"}]}}}