osquery-defense-kit/detection/evasion/name_path_mismatch.sql
2023-05-05 12:44:46 -04:00

111 lines
2.7 KiB
SQL

-- Processes that have an unrelated name in the process tree than the program on disk.
--
-- false positives:
-- * new software, particularly those using interpreted languages
--
-- references:
-- * https://attack.mitre.org/techniques/T1036/004/ (Masquerade Task or Service)
--
-- tags: persistent process
SELECT
SUBSTR(
COALESCE(
-- TODO: Fix to not require filename!
REGEX_MATCH (f.filename, '(.*?)\W', 1),
f.filename
),
0,
6
) AS short_filename,
COALESCE(REGEX_MATCH (p0.path, '.*/(.*)', 1), p0.path) AS basename,
COALESCE(
REGEX_MATCH (p0.path, '.*/([a-zA-Z]+)', 1),
p0.path
) AS base_letters,
CONCAT (
MIN(p0.euid, 500),
',',
COALESCE(REGEX_MATCH (p0.path, '.*/(.*)', 1), p0.path),
',',
p0.name
) AS exception_key,
-- Child
p0.pid AS p0_pid,
p0.path AS p0_path,
p0.name AS p0_name,
p0.cmdline AS p0_cmd,
p0.cwd AS p0_cwd,
p0.cgroup_path AS p0_cgroup,
p0.euid AS p0_euid,
p0_hash.sha256 AS p0_sha256,
-- Parent
p0.parent AS p1_pid,
p1.path AS p1_path,
p1.name AS p1_name,
p1.euid AS p1_euid,
p1.cmdline AS p1_cmd,
p1_hash.sha256 AS p1_sha256,
-- Grandparent
p1.parent AS p2_pid,
p2.name AS p2_name,
p2.path AS p2_path,
p2.cmdline AS p2_cmd,
p2_hash.sha256 AS p2_sha256
FROM
processes p0
LEFT JOIN file f ON p0.path = f.path
LEFT JOIN hash p0_hash ON p0.path = p0_hash.path
LEFT JOIN processes p1 ON p0.parent = p1.pid
LEFT JOIN hash p1_hash ON p1.path = p1_hash.path
LEFT JOIN processes p2 ON p1.parent = p2.pid
LEFT JOIN hash p2_hash ON p2.path = p2_hash.path
WHERE
p0.path != ''
AND NOT p0.name == basename
AND NOT (
LENGTH(basename) > 1
AND basename == short_filename
)
AND NOT (
LENGTH(p0.name) > 2
AND INSTR(LOWER(basename), LOWER(p0.name)) > 0
)
AND NOT (
LENGTH(short_filename) > 2
AND INSTR(LOWER(p0.name), LOWER(short_filename)) > 0
) -- Extremely common and unpredictable process name setters
AND NOT base_letters IN (
'bash',
'dash',
'electron',
'firefox',
'node',
'perl',
'python',
'ruby',
'thunderbird'
)
AND NOT exception_key IN (
'0,udevadm,systemd-udevd',
'0,udevadm,(udev-worker)',
'500,netcat,nc',
'120,systemd,(sd-pam)',
'500,busybox,sh',
'125,systemd,(sd-pam)',
'127,systemd,(sd-pam)',
'42,systemd,(sd-pam)',
'500,coreutils,tail',
'500,gjs-console,gnome-character',
'500,plugin-container,MainThread',
'500,pyrogenesis,main',
'500,rootlesskit,exe',
'500,rootlessport,exe',
'500,systemd,(sd-pam)',
'500,udevadm,systemd-udevd',
'500,vim.basic,vi'
)
AND NOT p0.path IN ('/usr/lib/systemd/systemd')
AND NOT p0_cgroup LIKE '/system.slice/docker-%'
GROUP by
exception_key