{"id":"CVE-2026-89749","title":"kernel: tracing: Fix crash passing ERR_PTR to kthread_stop() (CVE-2026-89749)","summary":"A flaw was found in the Linux kernel. Specifically, within the tracing subsystem, the `event_test_stuff()` function can pass an invalid error pointer to `kthread_stop()` if `kthread_run()` fails to create a kernel thread. This improper han…","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cvssSource":"vendor","cwe":"CWE-476","vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","affected":["enterprise_linux 10","enterprise_linux 6","enterprise_linux 7","enterprise_linux 8","enterprise_linux 9","openshift_container_platform 4"],"published":"2026-09-11","updated":"2026-09-15","sourceUpdated":"2026-09-15T08:13:21+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89749.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89749.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89749"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532518"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89749"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89749"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89749.mbox"},{"url":"https://git.kernel.org/stable/c/c1a4fb7aa290f158d50654d640292e49d9055fd1"},{"url":"https://git.kernel.org/stable/c/42ccb215ef0a552acbbd32f81009bfe4b278ba77"},{"url":"https://git.kernel.org/stable/c/98d06fb9865a490e12ebe32d65b9ffac6108614d"},{"url":"https://git.kernel.org/stable/c/ceb1707aef5824cf024eb82d10787b7621e2ff35"},{"url":"https://git.kernel.org/stable/c/12a499f741fc5be3731c8b0a0d909406575cc2eb"},{"url":"https://git.kernel.org/stable/c/adadf4192f700bca82abfda9fa6d58c0bf37cc04"},{"url":"https://git.kernel.org/stable/c/c40e0b4fa365969e67011529eabdfb66d1022256"},{"url":"https://git.kernel.org/stable/c/649bc7df3e5d7be6f7996a95084037dbf3cad1e5"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00211,"epssPercentile":0.11666,"ingestedAt":"2026-09-14T15:23:07.448Z","slug":"CVE-2026-89749","body":"## Overview\n\nA flaw was found in the Linux kernel. Specifically, within the tracing subsystem, the `event_test_stuff()` function can pass an invalid error pointer to `kthread_stop()` if `kthread_run()` fails to create a kernel thread. This improper handling of error pointers, particularly under memory pressure, leads to `kthread_stop()` attempting to dereference an invalid memory address. The consequence of this vulnerability is a kernel crash, resulting in a denial of service for the affected system.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Low · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, … · updated 2026-09-15 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89749.json)\n\n**kernel: tracing: Fix crash passing ERR_PTR to kthread_stop()** — rated Low by Red Hat. Released 2026-09-11, updated 2026-09-15.\n\nAffected:\n\n- Red Hat Enterprise Linux 10\n- Red Hat Enterprise Linux 6\n- Red Hat Enterprise Linux 7\n- Red Hat Enterprise Linux 8\n- Red Hat Enterprise Linux 9\n- Red Hat OpenShift Container Platform 4\n\nNo fix planned:\n\n- Red Hat Enterprise Linux 6\n- Red Hat Enterprise Linux 10\n- Red Hat Enterprise Linux 7\n- Red Hat Enterprise Linux 8\n- Red Hat Enterprise Linux 9\n- Red Hat OpenShift Container Platform 4\n\n## Remediation\n\nOut of support scope","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":203934,"id":"CVE-2026-89749","ts":1789490227922,"field":"cvss","old":null,"new":"5.5"},{"seq":203933,"id":"CVE-2026-89749","ts":1789490227922,"field":"severity","old":"none","new":"medium"},{"seq":147065,"id":"CVE-2026-89749","ts":1789270195020,"field":"cvss","old":null,"new":"4.4"},{"seq":147064,"id":"CVE-2026-89749","ts":1789270195020,"field":"severity","old":"none","new":"medium"}]}