osquery-defense-kit/detection/privesc/unexpected-privilege-escala...

90 lines
2.4 KiB
SQL

-- Find processes that run with a lower effective UID than their parent (state-based)
--
-- references:
-- * https://attack.mitre.org/techniques/T1548/001/ (Setuid and Setgid)
-- * https://cybersecurity.att.com/blogs/labs-research/shikitega-new-stealthy-malware-targeting-linux
--
-- related:
-- * unexpected-privilege-escalation-events.sql
--
-- tags: transient state process escalation
-- platform: linux
SELECT
p0.uid AS p0_uid,
-- 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_f.mode AS p1_mode,
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 hash p0_hash ON p0.path = p0_hash.path
LEFT JOIN processes p1 ON p0.parent = p1.pid
LEFT JOIN file p1_f ON p1.path = p1_f.path
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.pid IN (
SELECT
pid
FROM
processes
WHERE
euid < uid
AND NOT path IN (
'/bin/ps',
'/opt/1Password/1password',
'/usr/bin/doas',
'/usr/bin/fusermount',
'/usr/bin/fusermount3',
'/usr/bin/login',
'/usr/bin/su',
'/usr/bin/sudo',
'/usr/bin/top',
'/usr/libexec/Xorg',
'/usr/lib/xorg/Xorg'
) -- doas may be in the process of being upgraded
AND NOT path LIKE '/nix/store/%/bin/sudo'
AND NOT path LIKE '/nix/store/%/bin/dhcpcd'
AND NOT path LIKE '/snap/snapd/%/usr/lib/snapd/snap-confine'
AND NOT name IN ('doas', 'sudo')
)
AND NOT (
p0.cmdline LIKE '%pacman%'
AND p1.cmdline LIKE 'yay%'
)
AND NOT (
p0.name = 'polkit-agent-he'
AND p1.path = '/usr/bin/gnome-shell'
)
AND NOT (
p0.name = 'fusermount3'
AND p1.path = '/usr/lib/xdg-document-portal'
)
AND NOT (
p0.path = '/usr/bin/pkexec'
AND p1.path = '/usr/bin/update-notifier'
)
AND NOT (
p0.path = '/usr/libexec/xdg-permission-store'
AND p1.path = '/usr/lib/systemd/systemd'
)