{"id":"CVE-2026-89988","state":"PUBLISHED","title":"kprobes: Protect kprobe_blacklist with RCU","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nkprobes: Protect kprobe_blacklist with RCU\n\n__within_kprobe_blacklist() traverses kprobe_blacklist without holding\nkprobe_mutex. When a module is unloaded, kprobe_remove_area_blacklist()\nremoves blacklist entries and immediately frees them with kfree().\nA concurrent call to within_kprobe_blacklist() can therefore dereference\nfreed memory.\n\nFurthermore, within_kprobe_blacklist() can be called in atomic or\nnon-preemptible contexts where the sleeping kprobe_mutex cannot be taken.\n\nProtect kprobe_blacklist with RCU. Use guard(rcu)() and\nlist_for_each_entry_rcu() for traversal, list_add_tail_rcu() for\ninsertions, list_del_rcu() for deletions, and kfree_rcu() to reclaim\nentries safely after a grace period.","publishedAt":"2026-09-16T10:33:03.003Z","updatedAt":"2026-10-30T12:33:43.080Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"376e242429bf8539ef39a080ac113c8799840b13","status":"affected","lessThan":"3fb8386682ef4d0858c38bf0d8d8a47ba171fa23","versionType":"git"},{"version":"376e242429bf8539ef39a080ac113c8799840b13","status":"affected","lessThan":"5d97a13defc648c64d138145ace429b6a3d08943","versionType":"git"},{"version":"376e242429bf8539ef39a080ac113c8799840b13","status":"affected","lessThan":"8f406205003f741225f620f0e357ca0de71d45e3","versionType":"git"},{"version":"376e242429bf8539ef39a080ac113c8799840b13","status":"affected","lessThan":"630ed8734a02b992e8a97538179c2ece42c5210f","versionType":"git"},{"version":"376e242429bf8539ef39a080ac113c8799840b13","status":"affected","lessThan":"518d9b5568bb06f86e4434f7a30faa9612ea91ad","versionType":"git"},{"version":"376e242429bf8539ef39a080ac113c8799840b13","status":"affected","lessThan":"5da247e4d1e8661d4d6f997101d59967e8994e32","versionType":"git"},{"version":"376e242429bf8539ef39a080ac113c8799840b13","status":"affected","lessThan":"6e62cf983a2bd547e6bbd3f935539233e5f97f8f","versionType":"git"},{"version":"376e242429bf8539ef39a080ac113c8799840b13","status":"affected","lessThan":"0c4256196b3a105307e2235fbfd85e768bbcdd0f","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/kprobes.h","kernel/kprobes.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.16","versionType":"semver"},{"version":"5.10.273","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.224","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.51","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.5","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/kprobes.h","kernel/kprobes.c"]}],"references":["https://git.kernel.org/stable/c/3fb8386682ef4d0858c38bf0d8d8a47ba171fa23","https://git.kernel.org/stable/c/5d97a13defc648c64d138145ace429b6a3d08943","https://git.kernel.org/stable/c/8f406205003f741225f620f0e357ca0de71d45e3","https://git.kernel.org/stable/c/630ed8734a02b992e8a97538179c2ece42c5210f","https://git.kernel.org/stable/c/518d9b5568bb06f86e4434f7a30faa9612ea91ad","https://git.kernel.org/stable/c/5da247e4d1e8661d4d6f997101d59967e8994e32","https://git.kernel.org/stable/c/6e62cf983a2bd547e6bbd3f935539233e5f97f8f","https://git.kernel.org/stable/c/0c4256196b3a105307e2235fbfd85e768bbcdd0f"],"weaknesses":[],"ingestedAt":"2026-10-30T12:52:04.348Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/89xxx/CVE-2026-89988.json","commit":"1f312381e38164a43607eebab851b151dd16861e","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89988","state":"PUBLISHED","datePublished":"2026-09-16T10:33:03.003Z","dateUpdated":"2026-10-30T12:33:43.080Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-11T19:38:34.779Z"},"containers":{"cna":{"title":"kprobes: Protect kprobe_blacklist with RCU","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nkprobes: Protect kprobe_blacklist with RCU\n\n__within_kprobe_blacklist() traverses kprobe_blacklist without holding\nkprobe_mutex. When a module is unloaded, kprobe_remove_area_blacklist()\nremoves blacklist entries and immediately frees them with kfree().\nA concurrent call to within_kprobe_blacklist() can therefore dereference\nfreed memory.\n\nFurthermore, within_kprobe_blacklist() can be called in atomic or\nnon-preemptible contexts where the sleeping kprobe_mutex cannot be taken.\n\nProtect kprobe_blacklist with RCU. Use guard(rcu)() and\nlist_for_each_entry_rcu() for traversal, list_add_tail_rcu() for\ninsertions, list_del_rcu() for deletions, and kfree_rcu() to reclaim\nentries safely after a grace period."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"376e242429bf8539ef39a080ac113c8799840b13","status":"affected","lessThan":"3fb8386682ef4d0858c38bf0d8d8a47ba171fa23","versionType":"git"},{"version":"376e242429bf8539ef39a080ac113c8799840b13","status":"affected","lessThan":"5d97a13defc648c64d138145ace429b6a3d08943","versionType":"git"},{"version":"376e242429bf8539ef39a080ac113c8799840b13","status":"affected","lessThan":"8f406205003f741225f620f0e357ca0de71d45e3","versionType":"git"},{"version":"376e242429bf8539ef39a080ac113c8799840b13","status":"affected","lessThan":"630ed8734a02b992e8a97538179c2ece42c5210f","versionType":"git"},{"version":"376e242429bf8539ef39a080ac113c8799840b13","status":"affected","lessThan":"518d9b5568bb06f86e4434f7a30faa9612ea91ad","versionType":"git"},{"version":"376e242429bf8539ef39a080ac113c8799840b13","status":"affected","lessThan":"5da247e4d1e8661d4d6f997101d59967e8994e32","versionType":"git"},{"version":"376e242429bf8539ef39a080ac113c8799840b13","status":"affected","lessThan":"6e62cf983a2bd547e6bbd3f935539233e5f97f8f","versionType":"git"},{"version":"376e242429bf8539ef39a080ac113c8799840b13","status":"affected","lessThan":"0c4256196b3a105307e2235fbfd85e768bbcdd0f","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/kprobes.h","kernel/kprobes.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.16","versionType":"semver"},{"version":"5.10.273","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.224","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.51","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.5","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/kprobes.h","kernel/kprobes.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/3fb8386682ef4d0858c38bf0d8d8a47ba171fa23"},{"url":"https://git.kernel.org/stable/c/5d97a13defc648c64d138145ace429b6a3d08943"},{"url":"https://git.kernel.org/stable/c/8f406205003f741225f620f0e357ca0de71d45e3"},{"url":"https://git.kernel.org/stable/c/630ed8734a02b992e8a97538179c2ece42c5210f"},{"url":"https://git.kernel.org/stable/c/518d9b5568bb06f86e4434f7a30faa9612ea91ad"},{"url":"https://git.kernel.org/stable/c/5da247e4d1e8661d4d6f997101d59967e8994e32"},{"url":"https://git.kernel.org/stable/c/6e62cf983a2bd547e6bbd3f935539233e5f97f8f"},{"url":"https://git.kernel.org/stable/c/0c4256196b3a105307e2235fbfd85e768bbcdd0f"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The UAF is reached only via local syscalls: x86 perf_event_open() hardware execute breakpoints and register_kprobe() (tracefs, perf kprobes, BPF). It is not invoked from network packet processing or a remote service.\nAC:L - An attacker can loop the blacklist walk while concurrently causing module COMING/GOING so kprobe_remove_area_blacklist() does list_del/kfree, creating both sides of the race. Attacker-driven use-after-free races are AC:L.\nPR:L - x86 hw_breakpoint_arch_parse() calls within_kprobe_blacklist() for kernel execute breakpoints during perf_event_open() before hw_breakpoint_parse()'s CAP_SYS_ADMIN check, so an unprivileged user can trigger the walk. Module autoload via request_module() can mutate the list without CAP_SYS_MODULE.\nUI:N - The attacker triggers the race with their own syscalls (perf_event_open and module autoload/unload). No separate victim action is required.\nS:U - The bug is kernel-heap use-after-free in kprobes. Effects stay inside the kernel's security authority and do not cross a VM, IOMMU, or other boundary.\nC:H - Concurrent walk versus kfree of struct kprobe_blacklist_entry is a heap use-after-free. Reclaiming the object yields an arbitrary kernel read primitive, so confidentiality impact is high.\nI:H - A heap use-after-free on a list node is exploitable via heap spraying for an arbitrary write and control-flow hijack, so integrity impact is high.\nA:H - Following the freed blacklist entry's next pointer or fields causes a kernel oops or panic, taking down the system."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-30T12:33:43.080Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"5.10.273"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"5.15.224"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"6.18.51"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"7.2.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}