{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-72183 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-72183 is a high-severity vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-72183 and fix it if it is affected.\n\nWhat it is: CVE-2026-72183 is a high-severity vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-72183 in the wild and no public exploit code.\n\nAffected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-72183/ (Markdown: https://insights.sbomify.com/CVE-2026-72183/index.md)","id":"CVE-2026-72183","markdown":"https://insights.sbomify.com/CVE-2026-72183/index.md","name":"CVE-2026-72183","record":{"aliases":["BELL-CVE-2026-72183","DEBIAN-CVE-2026-72183","GHSA-5hcp-6cc5-jgx7","UBUNTU-CVE-2026-72183"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["privilege_escalation","denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A sandboxed process can bypass Landlock signal restrictions to kill or signal non-sandboxed processes via the SIGIO path.","user_interaction":"not_required","vuln_class":"security_feature_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":8.4,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H","version":"3.1"},"cwes":[],"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]","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"landlock: Fix LANDLOCK_SCOPE_SIGNAL bypass on the SIGIO path","id":"CVE-2026-72183","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"security_feature_bypass","year":"2026"},"n_packages":0,"n_references":4,"next":{"headline":"ntfs: fix hole runlist memory leak in insert range error path","id":"CVE-2026-72184"},"packages":[],"prev":{"headline":"power: supply: charger-manager: fix refcount leak in is_full_charged()","id":"CVE-2026-72182"},"products":["Linux"],"published":"2026-08-15","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-10-16","vendors":["Linux"]},"summary":"A sandboxed process can bypass Landlock signal restrictions to kill or signal non-sandboxed processes via the SIGIO path.","url":"https://insights.sbomify.com/CVE-2026-72183/"}