{"id":"CVE-2026-46259","title":"procfs: fix missing RCU protection when reading real_parent in do_task_stat()","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nprocfs: fix missing RCU protection when reading real_parent in do_task_stat()\n\nWhen reading /proc/[pid]/stat, do_task_stat() accesses task->real_parent\nwithout proper R…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 06fffb1267c9d986687b69d74a46ee332a50575e < fefa0fcd78be465b7ad4c497fa6ec90d64194c04","Linux >= 06fffb1267c9d986687b69d74a46ee332a50575e < c93a33f28f915d446eea6fb3f0e1def0b3af1982","Linux >= 06fffb1267c9d986687b69d74a46ee332a50575e < 1c8dc5b5517546c68ffae40b948336122bb61306","Linux >= 06fffb1267c9d986687b69d74a46ee332a50575e < 0e64bd46a04a4fd61279aca9f53a664e9e5f7e7e","Linux >= 06fffb1267c9d986687b69d74a46ee332a50575e < 73ec7c96601d61d52310c659145bb06d933a0fa6","Linux >= 06fffb1267c9d986687b69d74a46ee332a50575e < 4f9ae386861e280b7631ca252f798d25575627ee","Linux >= 06fffb1267c9d986687b69d74a46ee332a50575e < dd8b13cb4ff1a4545a214ed897fdf2bc341155b6","Linux >= 06fffb1267c9d986687b69d74a46ee332a50575e < 76149d53502cf17ef3ae454ff384551236fba867","Linux 2.6.26"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-16T15:21:25.410048Z"},"published":"2026-06-03","updated":"2026-10-16","sourceUpdated":"2026-10-16T15:31:14.530Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-46259","references":[{"url":"https://git.kernel.org/stable/c/fefa0fcd78be465b7ad4c497fa6ec90d64194c04"},{"url":"https://git.kernel.org/stable/c/c93a33f28f915d446eea6fb3f0e1def0b3af1982"},{"url":"https://git.kernel.org/stable/c/1c8dc5b5517546c68ffae40b948336122bb61306"},{"url":"https://git.kernel.org/stable/c/0e64bd46a04a4fd61279aca9f53a664e9e5f7e7e"},{"url":"https://git.kernel.org/stable/c/73ec7c96601d61d52310c659145bb06d933a0fa6"},{"url":"https://git.kernel.org/stable/c/4f9ae386861e280b7631ca252f798d25575627ee"},{"url":"https://git.kernel.org/stable/c/dd8b13cb4ff1a4545a214ed897fdf2bc341155b6"},{"url":"https://git.kernel.org/stable/c/76149d53502cf17ef3ae454ff384551236fba867"}],"tags":["cve.org"],"epss":0.00176,"epssPercentile":0.06636,"ingestedAt":"2026-10-16T17:24:46.713Z","slug":"CVE-2026-46259","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nprocfs: fix missing RCU protection when reading real_parent in do_task_stat()\n\nWhen reading /proc/[pid]/stat, do_task_stat() accesses task->real_parent\nwithout proper RCU protection, which leads to:\n\n  cpu 0                               cpu 1\n  -----                               -----\n  do_task_stat\n    var = task->real_parent\n                                      release_task\n                                        call_rcu(delayed_put_task_struct)\n    task_tgid_nr_ns(var)\n      rcu_read_lock   <--- Too late to protect task->real_parent!\n      task_pid_ptr    <--- UAF!\n      rcu_read_unlock\n\nThis patch uses task_ppid_nr_ns() instead of task_tgid_nr_ns() to add\nproper RCU protection for accessing task->real_parent.\n\n## Affected\n\n- `Linux >= 06fffb1267c9d986687b69d74a46ee332a50575e < fefa0fcd78be465b7ad4c497fa6ec90d64194c04`\n- `Linux >= 06fffb1267c9d986687b69d74a46ee332a50575e < c93a33f28f915d446eea6fb3f0e1def0b3af1982`\n- `Linux >= 06fffb1267c9d986687b69d74a46ee332a50575e < 1c8dc5b5517546c68ffae40b948336122bb61306`\n- `Linux >= 06fffb1267c9d986687b69d74a46ee332a50575e < 0e64bd46a04a4fd61279aca9f53a664e9e5f7e7e`\n- `Linux >= 06fffb1267c9d986687b69d74a46ee332a50575e < 73ec7c96601d61d52310c659145bb06d933a0fa6`\n- `Linux >= 06fffb1267c9d986687b69d74a46ee332a50575e < 4f9ae386861e280b7631ca252f798d25575627ee`\n- `Linux >= 06fffb1267c9d986687b69d74a46ee332a50575e < dd8b13cb4ff1a4545a214ed897fdf2bc341155b6`\n- `Linux >= 06fffb1267c9d986687b69d74a46ee332a50575e < 76149d53502cf17ef3ae454ff384551236fba867`\n- `Linux 2.6.26`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}