{"id":"CVE-2026-98037","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject untrusted allocated-object pointers\n\nWhen the final RCU read-side critical section ends, a local kptr is demoted\nto PTR_UNTRUSTED but retains MEM_ALLOC","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject untrusted allocated-object pointers\n\nWhen the final RCU read-side critical section ends, a local kptr is demoted\nto PTR_UNTRUSTED but retains MEM_ALLOC. The…","severity":"high","vendor":"Linux","product":"Linux","affected":["Linux >= 1b12171533a9bb23cf6fba7262b479028b65e1e8 < 092c2874dc1b2060fa77a465a971acd4fdf87683","Linux >= 1b12171533a9bb23cf6fba7262b479028b65e1e8 < 135d542b97fa93e32c457d49d6e7b33ca7d05bae","Linux >= 1b12171533a9bb23cf6fba7262b479028b65e1e8 < 6b1f786ad85a0b63393b76f5e634deab1a73198c","Linux >= 1b12171533a9bb23cf6fba7262b479028b65e1e8 < 7441ee8276641bddaf1cba7bb75ef9c1458ceb3b","Linux 6.8"],"published":"2026-09-25","updated":"2026-09-25","sourceUpdated":"2026-09-25T11:17:32.443","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-98037","references":[{"url":"https://git.kernel.org/stable/c/092c2874dc1b2060fa77a465a971acd4fdf87683","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/135d542b97fa93e32c457d49d6e7b33ca7d05bae","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6b1f786ad85a0b63393b76f5e634deab1a73198c","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7441ee8276641bddaf1cba7bb75ef9c1458ceb3b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98037.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-98037"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2541230"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98037"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98037"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98037.mbox"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"ingestedAt":"2026-09-25T11:06:38.850Z","epss":0.00201,"epssPercentile":0.09846,"cvss":7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","cvssSource":"vendor","cwe":["CWE-825"],"slug":"CVE-2026-98037","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject untrusted allocated-object pointers\n\nWhen the final RCU read-side critical section ends, a local kptr is demoted\nto PTR_UNTRUSTED but retains MEM_ALLOC. The pointer may be NULL or may refer\nto an object whose lifetime is no longer protected.\n\ntype_is_ptr_alloc_obj() nevertheless recognizes any PTR_TO_BTF_ID with\nMEM_ALLOC as a live allocated object. In particular, a refcount-only local\nkptr never carries NON_OWN_REF, so it still passes the\nbpf_refcount_acquire() argument check after RCU protection ends. The kfunc\ncan then dereference NULL or stale memory.\n\nMake type_is_ptr_alloc_obj() reject PTR_UNTRUSTED pointers. Since\ntype_is_non_owning_ref() is based on the same predicate, graph kfunc\narguments obey the same live-object requirement. Fault-protected reads of\nthe demoted pointer remain valid: writes are already rejected, and read\nfixups use bpf_may_fault_on_deref() rather than this predicate.\n\n[ kkd: Rewrote commit log ]\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-09-28 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98037.json)","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":38.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":212430,"id":"CVE-2026-98037","ts":1790668182435,"field":"cvss","old":null,"new":"7"},{"seq":212429,"id":"CVE-2026-98037","ts":1790668182435,"field":"severity","old":"none","new":"high"}]}