--- id: CVE-2026-98260 title: |- In the Linux kernel, the following vulnerability has been resolved: exec: Cleanup POSIX timers right after de_thread() A per-thread CPU timer holds a reference to the PID of the thread it is attached to and, while it is armed, its node… summary: |- In the Linux kernel, the following vulnerability has been resolved: exec: Cleanup POSIX timers right after de_thread() A per-thread CPU timer holds a reference to the PID of the thread it is attached to and, while it is armed, its node… 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' vendor: Linux product: Linux affected: - >- Linux >= 55e8c8eb2c7b6bf30e99423ccfe7ca032f498f59 < 6f1977cea3e85cd8ab55fb337d3e1725fe61d1ce - >- Linux >= 55e8c8eb2c7b6bf30e99423ccfe7ca032f498f59 < d9ae467e617ca29b825493a362bf0d75ad5f4ac3 - >- Linux >= 55e8c8eb2c7b6bf30e99423ccfe7ca032f498f59 < 75aa08b93c65766040f9ca99f41ac85ad22596b6 - >- Linux >= 55e8c8eb2c7b6bf30e99423ccfe7ca032f498f59 < d602877baf36c43c788a5f472c977e0be414029f - >- Linux >= 55e8c8eb2c7b6bf30e99423ccfe7ca032f498f59 < acb03d3881818581052924a9bbbe92b8741ed448 - Linux 5.7 published: '2026-10-06' updated: '2026-10-07' sourceUpdated: '2026-10-07T07:17:07.260' source: NVD sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98260' references: - url: 'https://git.kernel.org/stable/c/6f1977cea3e85cd8ab55fb337d3e1725fe61d1ce' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/75aa08b93c65766040f9ca99f41ac85ad22596b6' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/acb03d3881818581052924a9bbbe92b8741ed448' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/d602877baf36c43c788a5f472c977e0be414029f' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/d9ae467e617ca29b825493a362bf0d75ad5f4ac3' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: >- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98260.json - url: 'https://access.redhat.com/security/cve/CVE-2026-98260' - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2546491' - url: 'https://www.cve.org/CVERecord?id=CVE-2026-98260' - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98260' - url: >- https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98260.mbox - url: 'https://access.redhat.com/errata/RHSA-2026:83707' - url: 'https://access.redhat.com/errata/RHSA-2026:83738' - url: 'https://access.redhat.com/errata/RHSA-2026:83797' - url: 'https://access.redhat.com/errata/RHSA-2026:83775' - url: 'https://access.redhat.com/errata/RHSA-2026:83739' - url: 'https://access.redhat.com/errata/RHSA-2026:85321' - url: 'https://access.redhat.com/errata/RHSA-2026:86033' tags: - nvd - cve.org - csaf - vex - red-hat - exploit-available epss: 0.00184 epssPercentile: 0.07912 ingestedAt: '2026-10-06T08:50:17.427Z' cwe: - CWE-825 patched: - enterprise_linux_appstream_eus_v_10_0 - enterprise_linux_appstream_e4s_v_9_2 - enterprise_linux_appstream_e4s_v_9_4 - enterprise_linux_appstream_eus_v_9_6 - enterprise_linux_baseos_eus_v_10_0 - enterprise_linux_baseos_e4s_v_9_2 - enterprise_linux_baseos_e4s_v_9_4 - enterprise_linux_baseos_eus_v_9_6 - enterprise_linux_codeready_linux_builder_eus_v_10_0 - codeready_linux_builder_eus_v_9_6 - enterprise_linux_real_time_for_nfv_eus_v_10_0 - enterprise_linux_real_time_for_nfv_e4s_v_9_2 - enterprise_linux_real_time_for_nfv_e4s_v_9_4 - enterprise_linux_real_time_for_nfv_eus_v_9_6 - enterprise_linux_real_time_eus_v_10_0 - enterprise_linux_real_time_e4s_v_9_2 - enterprise_linux_real_time_e4s_v_9_4 - enterprise_linux_real_time_eus_v_9_6 exploits: github: 14 githubRepos: - 'https://github.com/zsw125/o3root' - 'https://github.com/ylh440104/InfinityCore-Android-CVE-2026-98260' - 'https://github.com/quyicheng03-boop/CVE-2026-98260-popsicle-android' checkedAt: '2026-10-27T19:25:30.012Z' exploitAvailable: true --- ## Overview In the Linux kernel, the following vulnerability has been resolved: exec: Cleanup POSIX timers right after de_thread() A per-thread CPU timer holds a reference to the PID of the thread it is attached to and, while it is armed, its node is queued in that thread's posix_cputimers. The task is looked up by that PID. When a non-leader thread exec()s, de_thread() changes which task owns that PID. pid_task(timer->it.cpu.pid, PIDTYPE_PID) then returns NULL, but the node is still queued on tsk, which is alive. timer_lock_sighand() takes a failed lookup to mean that the node is already dequeued, so it has nothing to undo. begin_new_exec() calls posix_cpu_timers_exit(me) right after exec_task_namespaces() and that removes the leftover node, so the state normally stays invisible. But bprm->point_of_no_return is set before de_thread(), so if unshare_files(), set_mm_exe_file(), exec_mmap() or exec_task_namespaces() fails, the task dies before it gets there. exit_itimers() then frees the k_itimer while its node is still queued, and reaping tsk later erases that freed node from the rbtree. In short: the non-leader thread B the parent timer_create(CLOCK_THREAD_CPUTIME_ID) timer_settime() arm_timer() // the node is queued on B execve() de_thread(B) exchange_tids(B, leader) // B's PID now belongs to the leader release_task(leader) __exit_signal(leader) posix_cpu_timers_exit(leader) // cleans leader's queue, not B's __unhash_process(leader) // that PID has no task anymore exec_mmap() mmap_read_lock_killable(old_mm) kill(B, SIGKILL) // -EINTR get_signal() do_exit() exit_itimers() posix_timer_delete() posix_cpu_timer_del() posix_timer_unhash_and_free() // freed while still queued wait4() release_task(B) posix_cpu_timers_exit(B) cleanup_timerqueue() timerqueue_del() // use-after-free Move the POSIX timer cleanup right after de_thread() before any of the later failure conditions brings the task into do_exit(). [ tglx: Move the cleanup right after de_thread() ] ## Remediation Refer to the linked advisories for vendor-supplied fixes and affected version ranges. ## Vendor advisories - **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 9 · updated 2026-10-20 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98260.json) - **RHSA-2026:83707** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux BaseOS EUS (v. 10.0), Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0), Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0), Red Hat Enterprise Linux Real Time EUS (v. 10.0) · released 2026-10-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:83707) - **RHSA-2026:83738** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.2), Red Hat Enterprise Linux BaseOS E4S (v.9.2) · released 2026-10-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:83738) - **RHSA-2026:83797** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.4), Red Hat Enterprise Linux BaseOS E4S (v.9.4), Red Hat Enterprise Linux Real Time for NFV E4S (v.9.4), Red Hat Enterprise Linux Real Time E4S (v.9.4) · released 2026-10-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:83797) - **RHSA-2026:83775** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v.9.6), Red Hat Enterprise Linux BaseOS EUS (v.9.6), Red Hat CodeReady Linux Builder EUS (v.9.6), Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6), Red Hat Enterprise Linux Real Time EUS (v.9.6) · released 2026-10-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:83775) - **RHSA-2026:83739** · Red Hat · fixed in: Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2), Red Hat Enterprise Linux Real Time E4S (v.9.2) · released 2026-10-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:83739) - **RHSA-2026:85321** · Red Hat · fixed in: 10Base-SMTV, Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10), Red Hat Enterprise Linux Hidden (v. 10), Red Hat Enterprise Linux Real Time for NFV (v. 10), … · released 2026-10-19 · [advisory](https://access.redhat.com/errata/RHSA-2026:85321) - **RHSA-2026:86033** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9), Red Hat Enterprise Linux Real Time for NFV (v. 9), Red Hat Enterprise Linux Real Time (v. 9) · released 2026-10-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:86033)