{"id":"AZL-55195","summary":"CVE-2024-56549 affecting package kernel for versions less than 6.6.78.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ncachefiles: Fix NULL pointer dereference in object-\u003efile\n\nAt present, the object-\u003efile has the NULL pointer dereference problem in\nondemand-mode. The root cause is that the allocated fd and object-\u003efile\nlifetime are inconsistent, and the user-space invocation to anon_fd uses\nobject-\u003efile. Following is the process that triggers the issue:\n\n\t  [write fd]\t\t\t\t[umount]\ncachefiles_ondemand_fd_write_iter\n\t\t\t\t       fscache_cookie_state_machine\n\t\t\t\t\t cachefiles_withdraw_cookie\n  if (!file) return -ENOBUFS\n\t\t\t\t\t   cachefiles_clean_up_object\n\t\t\t\t\t     cachefiles_unmark_inode_in_use\n\t\t\t\t\t     fput(object-\u003efile)\n\t\t\t\t\t     object-\u003efile = NULL\n  // file NULL pointer dereference!\n  __cachefiles_write(..., file, ...)\n\nFix this issue by add an additional reference count to the object-\u003efile\nbefore write/llseek, and decrement after it finished.","modified":"2026-04-01T05:18:31.961094Z","published":"2024-12-27T14:15:34Z","upstream":["CVE-2024-56549"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-56549"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.78.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-55195.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}