{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-74637 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-74637 is a high-severity use after free vulnerability in Linux, published on 22 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-2026-74637 and fix it if it is affected.\n\nWhat it is: CVE-2026-74637 is a high-severity use after free vulnerability in Linux, published on 22 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-2026-74637 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-2026-74637/ (Markdown: https://insights.sbomify.com/CVE-2026-74637/index.md)","id":"CVE-2026-74637","markdown":"https://insights.sbomify.com/CVE-2026-74637/index.md","name":"CVE-2026-74637","record":{"aliases":["AZL-97353","BELL-CVE-2026-74637","DEBIAN-CVE-2026-74637","GHSA-f4j9-rgf4-2rmj","UBUNTU-CVE-2026-74637"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["code_execution","privilege_escalation"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A use-after-free in the Linux kernel perf subsystem allows local attackers to execute arbitrary code or escalate privileges via CPU hotplug events.","user_interaction":"not_required","vuln_class":"use_after_free"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":7.8,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf/core: Fix group leader use-after-free after sibling detach\n\nperf_group_detach() handles leader and sibling detach differently. When the\ngroup leader is detached, all siblings are promoted to singleton events and\ntheir group_leader pointer is reset to themselves. When a sibling is\ndetached, it is removed from the leader's sibling_list, but its\ngroup_leader pointer is left pointing at the old leader.\n\nThat is harmless when the sibling is being closed and freed immediately, as\nin the DETACH_DEAD path. It is not safe when the sibling is detached but\nkept alive, such as during CPU hotplug with DETACH_GROUP. In that case the\nsibling is removed from the context, while its file descriptor can still\nkeep it alive.\n\nA typical failing sequence is:\n\n  - A group contains leader L and sibling S.\n  - CPU hot-unplug detaches S with DETACH_GROUP, removing it from\n    L-\u003esibling_list but leaving S-\u003egroup_leader == L.\n  - L is later closed and freed.\n  - A PERF_IOC_FLAG_GROUP ioctl on S follows S-\u003egroup_leader and\n    dereferences the freed leader.\n\nThis was reproduced by running the perf event fuzzer, CPU hotplug, and a\nstress workload concurrently:\n\n  Unable to handle kernel paging request at virtual address 006b6b6b6b6b6cdb\n  CPU: 2 PID: 12489 Comm: perf_fuzzer 6.18.7 PREEMPT\n  pc : perf_ioctl+0x34c/0xc68\n  x20: ffffff89a3fa2c70 x8 : 6b6b6b6b6b6b6b6b\n  Code: 943c4a0e 340047a0 f9404a94 f9411e88 (f940b908)\n  Call trace:\n  perf_ioctl+0x34c/0xc68 (P)\n  __arm64_sys_ioctl+0xa0/0xf4\n  invoke_syscall+0x58/0xe4\n  el0_svc_common+0xa8/0xdc\n  do_el0_svc+0x1c/0x28\n  el0_svc+0x40/0xc0\n  el0t_64_sync_handler+0x68/0xdc\n  el0t_64_sync+0x1c4/0x1c8\n\nThe fault happened in perf_ioctl(), where perf_event_for_each() follows\nthe stale group_leader pointer and perf_event_for_each_child() then\ndereferences the freed leader's context.\n\nFix the use-after-free by promoting the detached sibling to a singleton.\nAlso fix __event_disable() cgroup accounting and event state change.","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":"perf/core: Fix group leader use-after-free after sibling detach","id":"CVE-2026-74637","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"use_after_free","year":"2026"},"n_packages":0,"n_references":8,"next":{"headline":"drm/v3d: Serialize the scheduler timeout handlers","id":"CVE-2026-74638"},"packages":[],"prev":{"headline":"tracing: Fix race between update_event_fields and, event_define_fields","id":"CVE-2026-74636"},"products":["Linux"],"published":"2026-08-22","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":"total"},"state":"PUBLISHED","updated":"2026-10-16","vendors":["Linux"]},"summary":"A use-after-free in the Linux kernel perf subsystem allows local attackers to execute arbitrary code or escalate privileges via CPU hotplug events.","url":"https://insights.sbomify.com/CVE-2026-74637/"}