147 lines
4.6 KiB
Markdown
147 lines
4.6 KiB
Markdown
# CUJO
|
|
|
|
- [device](#device)
|
|
- [digging](#digging)
|
|
- [nmap](#nmap)
|
|
- [sniffing](#sniffing)
|
|
- [impersonating](#impersonating)
|
|
- [phone home](#phone-home)
|
|
|
|
## TV
|
|
name|value
|
|
----|-----
|
|
model|TODO
|
|
product|`TODO`
|
|
firmware|`TODO`
|
|
features|TODO
|
|
vulnerabilities|all phone-home calls are done over `HTTP`
|
|
|
|
|
|
## digging
|
|
|
|
### nmap
|
|
|
|
from `nmap -PN -sV <device>`, we get:
|
|
|
|
```
|
|
<TODO all ports are closed>
|
|
```
|
|
|
|
### sniffing
|
|
|
|
watching the network activity of the device (`192.168.1.108`), noticed it tried to resolve:
|
|
|
|
* agent.cujo.io
|
|
* jenkins.getcujo.com
|
|
|
|
but since the network isn't allowing external traffic, the DNS resolution fails.
|
|
|
|
the device continues to retry this, but takes no other action.
|
|
|
|
using `dnsmasq`, spoof these addresses to something under out control (`192.168.1.106`), and now we see:
|
|
|
|
```
|
|
Frame 125229: 74 bytes on wire (592 bits), 74 bytes captured (592 bits)
|
|
Ethernet II, Src: 192.168.1.108 (cc:d3:1e:d0:20:67), Dst: 192.168.1.106 (f4:0f:24:04:2e:8f)
|
|
Internet Protocol Version 4, Src: 192.168.1.108 (192.168.1.108), Dst: agent.cujo.io (192.168.1.106)
|
|
Transmission Control Protocol, Src Port: 53455 (53455), Dst Port: 9443 (9443), Seq: 0, Len: 0
|
|
Source Port: 53455
|
|
Destination Port: 9443
|
|
[Stream index: 14]
|
|
[TCP Segment Len: 0]
|
|
Sequence number: 0 (relative sequence number)
|
|
Acknowledgment number: 0
|
|
Header Length: 40 bytes
|
|
Flags: 0x002 (SYN)
|
|
Window size value: 14600
|
|
[Calculated window size: 14600]
|
|
Checksum: 0xaf14 [validation disabled]
|
|
Urgent pointer: 0
|
|
Options: (20 bytes), Maximum segment size, SACK permitted, Timestamps, No-Operation (NOP), Window scale
|
|
Maximum segment size: 1460 bytes
|
|
Kind: Maximum Segment Size (2)
|
|
Length: 4
|
|
MSS Value: 1460
|
|
TCP SACK Permitted Option: True
|
|
Timestamps: TSval 51225, TSecr 0
|
|
No-Operation (NOP)
|
|
Window scale: 5 (multiply by 32)
|
|
|
|
```
|
|
|
|
now we can see it is making some empty TCP request to `9443`
|
|
|
|
## impersonating
|
|
|
|
### phone home
|
|
|
|
standing up a webserver on `9443`, we start to see traffic:
|
|
|
|
```
|
|
\x16\x03\x01\x02\x00\x01\x00\x01\xfc\x03\x03\xa1\xe1\x9d\x08\x88]*\xce\xe7G
|
|
```
|
|
|
|
```
|
|
\x16\x03\x01\x02\x00\x01\x00\x01\xfc\x03\x03Gg\xed\xa3m\x02\x88\xbd\xf0\xd1\x1eS\xf0\xfbc\xfb\x80K\x8dD\xed\xfb\x9b\x8c\xa0\xb2\xc6C\xc8\x15\x86\xbb\x00\x00\xa0\xc00\xc0,\xc0(\xc0$\xc0\x14\xc0
|
|
```
|
|
|
|
requests starting with `\x16\x03\x01` are almost certainly HTTPS requests coming over HTTP, so try to forge a usable cert:
|
|
|
|
```
|
|
$ openssl req -x509 -newkey rsa:2048 -keyout agents.cujo.io.pem -out agents.cujo.io.pem -days 365 -nodes
|
|
Generating a 2048 bit RSA private key
|
|
........................................................................................+++
|
|
..........................................................................................................+++
|
|
writing new private key to 'agents.cujo.io.pem'
|
|
-----
|
|
You are about to be asked to enter information that will be incorporated
|
|
into your certificate request.
|
|
What you are about to enter is what is called a Distinguished Name or a DN.
|
|
There are quite a few fields but you can leave some blank
|
|
For some fields there will be a default value,
|
|
If you enter '.', the field will be left blank.
|
|
-----
|
|
Country Name (2 letter code) [AU]:US
|
|
State or Province Name (full name) [Some-State]:California
|
|
Locality Name (eg, city) []:Los Angeles
|
|
Organization Name (eg, company) [Internet Widgits Pty Ltd]:CUJO
|
|
Organizational Unit Name (eg, section) []:
|
|
Common Name (e.g. server FQDN or YOUR name) []:agent.cujo.io
|
|
Email Address []:
|
|
|
|
$ openssl x509 -text -in agents.cujo.io.pem
|
|
Certificate:
|
|
Data:
|
|
Version: 3 (0x2)
|
|
Serial Number:
|
|
e6:5b:e3:de:c4:4f:13:7e
|
|
Signature Algorithm: sha1WithRSAEncryption
|
|
Issuer: C=US, ST=California, L=Los Angeles, O=CUJO, CN=agent.cujo.io
|
|
Validity
|
|
Not Before: Nov 29 01:38:50 2016 GMT
|
|
Not After : Nov 29 01:38:50 2017 GMT
|
|
Subject: C=US, ST=California, L=Los Angeles, O=CUJO, CN=agent.cujo.io
|
|
Subject Public Key Info:
|
|
Public Key Algorithm: rsaEncryption
|
|
RSA Public Key: (2048 bit)
|
|
Modulus (2048 bit):
|
|
...
|
|
Exponent: 65537 (0x10001)
|
|
X509v3 extensions:
|
|
X509v3 Subject Key Identifier:
|
|
B2:33:5E:3A:3D:6E:B8:DC:D8:19:89:A2:B5:67:1C:99:B1:B0:2F:2F
|
|
X509v3 Authority Key Identifier:
|
|
keyid:...
|
|
DirName:/C=US/ST=California/L=Los Angeles/O=CUJO/CN=agent.cujo.io
|
|
serial:...
|
|
|
|
X509v3 Basic Constraints:
|
|
CA:TRUE
|
|
Signature Algorithm: sha1WithRSAEncryption
|
|
...
|
|
-----BEGIN CERTIFICATE-----
|
|
...
|
|
-----END CERTIFICATE-----
|
|
```
|
|
|