{"id":"AZL-109094","summary":"CVE-2026-98775 affecting package kernel 6.6.157.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnitro_enclaves: fix use-after-free on SLOT_ALLOC failure\n\nWhen ne_create_vm_ioctl() fails the SLOT_ALLOC request after\nanon_inode_getfile() has succeeded, the error path calls\nfput(enclave_file) and then frees ne_enclave.\n\nIn normal userspace context, fput() defers the final __fput() via\ntask_work. ne_enclave_release() therefore runs after ne_enclave has\nalready been freed and dereferences ne_enclave-\u003eslot_uid, causing a\nuse-after-free: KASAN: slab-use-after-free in ne_enclave_release.\n\nThe enclave has no slot allocated and is not yet linked into the\nenclaves list on this error path, so ne_enclave_release() is expected\nto return early when slot_uid is zero. However, reading slot_uid\nalready accesses the freed object.\n\nClear enclave_file-\u003eprivate_data before fput() on the error path.\nne_enclave_release() then returns immediately when private_data is\nNULL, leaving the ioctl error path as the sole owner of ne_enclave.\nThis is safe because the file has not been fd_install()'d yet.\n\nTested on an AWS EC2 m5.2xlarge with CONFIG_KASAN=y. Without the\npatch, the reproducer triggers a KASAN slab-use-after-free on every\nSLOT_ALLOC failure. With the patch, no KASAN report is produced and\nthe SLOT_ALLOC error is still returned. Normal enclave creation and\nteardown are unaffected.","modified":"2026-10-19T14:16:11.584957511Z","published":"2026-10-18T16:17:31Z","upstream":["CVE-2026-98775"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98775"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.157.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-109094.json"}}],"schema_version":"1.9.0"}