{"id":"AZL-90759","summary":"CVE-2026-53106 affecting package kernel 6.6.150.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Do not allow deleting local storage in NMI\n\nCurrently, local storage may deadlock when deferring freeing selem or\nlocal storage through kfree_rcu(), call_rcu() or call_rcu_tasks_trace()\nin NMI or reentrant. Since deleting selem in NMI is an unlikely use\ncase, partially mitigate it by returning error when calling from\nbpf_xxx_storage_delete() helpers in NMI. Note that, it is still possible\nto deadlock through reentrant. A full mitigation requires returning\nerror when irqs_disabled() is true, which, however is too heavy-handed\nfor bpf_xxx_storage_delete().\n\nThe long-term solution requires _nolock versions of call_rcu. Another\npossible solution is to defer the free through irq_work [0], but it\nwould grow the size of selem, which is non-ideal.\n\nThe check is only needed in bpf_selem_unlink(), which is used by helpers\nand syscalls. bpf_selem_unlink_nofail() is fine as it is called during\nmap and owner tear down that never run in NMI or reentrant.\n\n[0] https://lore.kernel.org/bpf/20260205190233.912-1-alexei.starovoitov@gmail.com/","modified":"2026-08-31T05:26:27Z","published":"2026-06-24T17:17:24Z","upstream":["CVE-2026-53106"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53106"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.150.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-90759.json"}}],"schema_version":"1.9.0"}