diff --git a/detection/execution/unexpected-xattr-calls-macos.sql b/detection/execution/unexpected-xattr-calls-macos.sql new file mode 100644 index 0000000..6bc2b2c --- /dev/null +++ b/detection/execution/unexpected-xattr-calls-macos.sql @@ -0,0 +1,59 @@ +-- Detect unusual calls to xattr, used to remove filesystem attributes +-- +-- false positives: +-- * none observed, but they are expected +-- +-- interval: 300 +-- platform: darwin +-- tags: process events +SELECT pe.path AS path, + REGEX_MATCH (pe.path, '.*/(.*)', 1) AS name, + TRIM(pe.cmdline) AS cmd, + pe.pid AS pid, + pe.euid AS euid, + pe.parent AS parent_pid, + TRIM(IIF(pp.cmdline != NULL, pp.cmdline, ppe.cmdline)) AS parent_cmd, + TRIM(IIF(pp.path != NULL, pp.path, ppe.path)) AS parent_path, + REGEX_MATCH ( + IIF(pp.path != NULL, pp.path, ppe.path), + '.*/(.*)', + 1 + ) AS parent_name, + TRIM(IIF(pp.path != NULL, hash.sha256, ehash.sha256)) AS parent_hash, + TRIM(IIF(gp.cmdline != NULL, gp.cmdline, gpe.cmdline)) AS gparent_cmd, + TRIM(IIF(gp.path != NULL, gp.path, gpe.path)) AS gparent_path, + REGEX_MATCH ( + IIF(gp.path != NULL, gp.path, gpe.path), + '.*/(.*)', + 1 + ) AS gparent_name, + IIF(pp.parent != NULL, pp.parent, ppe.parent) AS gparent_pid, + IIF( + signature.identifier != NULL, + signature.identifier, + esignature.identifier + ) AS parent_identifier, + IIF( + signature.authority != NULL, + signature.authority, + esignature.authority + ) AS parent_authority +FROM process_events pe + LEFT JOIN processes p ON pe.pid = p.pid + LEFT JOIN processes pp ON pe.parent = pp.pid + LEFT JOIN process_events ppe ON pe.parent = ppe.pid + LEFT JOIN processes gp ON gp.pid = pp.parent + LEFT JOIN process_events gpe ON ppe.parent = gpe.pid + LEFT JOIN hash ON pp.path = hash.path + LEFT JOIN hash ehash ON ppe.path = ehash.path + LEFT JOIN signature ON pp.path = signature.path + LEFT JOIN signature esignature ON ppe.path = esignature.path +WHERE pe.path = '/usr/bin/xattr' + AND pe.time > (strftime('%s', 'now') -300) + AND NOT ( + pe.euid > 500 AND + cmd LIKE '%xattr -l %' + ) +GROUP BY pe.pid + +