{"id":"AZL-73132","summary":"CVE-2025-68740 affecting package kernel for versions less than 6.6.121.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nima: Handle error code returned by ima_filter_rule_match()\n\nIn ima_match_rules(), if ima_filter_rule_match() returns -ENOENT due to\nthe rule being NULL, the function incorrectly skips the 'if (!rc)' check\nand sets 'result = true'. The LSM rule is considered a match, causing\nextra files to be measured by IMA.\n\nThis issue can be reproduced in the following scenario:\nAfter unloading the SELinux policy module via 'semodule -d', if an IMA\nmeasurement is triggered before ima_lsm_rules is updated,\nin ima_match_rules(), the first call to ima_filter_rule_match() returns\n-ESTALE. This causes the code to enter the 'if (rc == -ESTALE &&\n!rule_reinitialized)' block, perform ima_lsm_copy_rule() and retry. In\nima_lsm_copy_rule(), since the SELinux module has been removed, the rule\nbecomes NULL, and the second call to ima_filter_rule_match() returns\n-ENOENT. This bypasses the 'if (!rc)' check and results in a false match.\n\nCall trace:\n  selinux_audit_rule_match+0x310/0x3b8\n  security_audit_rule_match+0x60/0xa0\n  ima_match_rules+0x2e4/0x4a0\n  ima_match_policy+0x9c/0x1e8\n  ima_get_action+0x48/0x60\n  process_measurement+0xf8/0xa98\n  ima_bprm_check+0x98/0xd8\n  security_bprm_check+0x5c/0x78\n  search_binary_handler+0x6c/0x318\n  exec_binprm+0x58/0x1b8\n  bprm_execve+0xb8/0x130\n  do_execveat_common.isra.0+0x1a8/0x258\n  __arm64_sys_execve+0x48/0x68\n  invoke_syscall+0x50/0x128\n  el0_svc_common.constprop.0+0xc8/0xf0\n  do_el0_svc+0x24/0x38\n  el0_svc+0x44/0x200\n  el0t_64_sync_handler+0x100/0x130\n  el0t_64_sync+0x3c8/0x3d0\n\nFix this by changing 'if (!rc)' to 'if (rc \u003c= 0)' to ensure that error\ncodes like -ENOENT do not bypass the check and accidentally result in a\nsuccessful match.","modified":"2026-04-01T05:22:15.566655Z","published":"2025-12-24T13:16:28Z","upstream":["CVE-2025-68740"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-68740"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.121.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-73132.json"}}],"schema_version":"1.7.5"}