NSA and VPN

NSA and VPNs

A recent article on [Der Spiegel] show lots of new attacks

SSL/TLS

PPTP

IPSEC

SSH

http://www.spiegel.de/international/world/nsa-documents-attacks-on-vpn-ssl-tls-ssh-tor-a-1010525.html

The Program

Falls under the "Office of Target Pursuit" (OTP)

Named OTP VPN Exploitation Team

Now called OTTERCREAK

TOYGRIPPE: repository of VPN metadata of systems of interest

• includes machine fingerprint and the VPN service connected to (e.g. PIA)

BLEAKINQUIRY: repository of potentially exploitable VPNs

• unclear if this means list of VPNs on the internet, or common configurations

XKEYSCORE: common source of VPNs to exploit but includes random people like you and I

• don't use it as a primary attack source unless necessary due to legal hoops they have to go through

The Workflow

Analyst targets someone (e.g. me) and find that it's using a VPN

Analyst must come up with a way to collect inbound and outbound traffic of the target

Calls up OTP VPN Exploit Team

They look at the metadata (traffic fingerprinting), define the attacks, and search through collection sources

• TOYGRIPPE: has a list of all the VPN metadata• PINWALE: long term collection of “SIGINT”• XKEYSCORE: raw packet captures from everyone• VULCANDEATHGRIP: raw packet captures for VPNs• FOURSCORE: repo for PPTP• CORALREEF: database of PSKs for VPNs

Decrypt traffic and return the results (passive or active)

TOYGRIPPE

Lets an analyst search through tons of metadata from a variety of collection sources

• MUSCULAR• UKJ-260D??

Focused on IPSec, PPTP, and ViPNet (Vodaphone)

Example of using TOYGRIPPE to find VPN metadata

IR = IRAN

S = source port 1037

Sites where the data was collected

IPSEC Review

IPSEC VPNs are the most common in enterprise environments

Uses a Pre Shared Key (PSK) or a Public Key cert (PK)

ISAKMP/IKE packets perform a handshake for a temporary key for your session

ESP packets are the actual encrypted data

Example IPSEC: FTM 1

“Follow the Money” FTM target 1

Implanted keyloggers and other hardware but it didn’t work

Called up TAO who owned them and recovered the configuration files of the VPN including PSKs

• Can now “passively exploit” which should mean decrypt VPN traffic

Example IPSEC: FTM 2

TAO owns the router

Network Security Products “implant” allows passive exploitation

• This implies that it’s a way of collecting the temporary keys (IKE/ISAKMP) values• Maybe making them predictable or fucking up their handshake

Results in ESP packets being decrypted raw

PPTP Review

Microsoft Point To Point Tunneling Protocol

Owned years ago by Moxie and others

Outdated but still used

Control channel operates on 1723

Data channel is sometimes port 47 (GRE-Next Protol)

Example PPTP: Airlines, Telcos, Governments

The slides just list all of these sites that have been owned, implying that they have a protocol level exploit

Iran Air

Royal Jordanian Air

Transaero Airlines

Mexican Embassy

Pakistani General Intelligence

Turkish Embassy

Afghanistan Government (apparently the whole thing)

More Example PPTP

Zaad Financial bank

Kabul lBank

BNI Banking Indonesia

And so on…

TL;DL

These files are from at around 4-2011 and some of them are older

Most of the exploitations are not VPN destroying, just concerning

The team seems mainly to implement attacks using other people’s exploits

• Decrypt TLS when TAO collects the private keys• Decrypt IPSEC when the PSK is discovered• Decrypt SSH when the private keys are found

They (probably) can’t…

• Own all VPNs with a single click• Own your personal VPN• Own SSH and TLS automatically

TL;DL: They Can…probably

See that you are on a VPN, which VPN, and if that VPN has an exploit

Own you completely via PPTP

Capture your VPN traffic and try to decrypt it later

Call up TAO or NSP to implant something on your network that would make your VPN owned

Decrypt SSH tunnels with the help of TAO or NSP

Decrypt SSL/TLS tunnels with the help of TAO or NSP

Lookup your router and see if there is an exploit for it

Pay attention to large VPN providers to exploit them including your traffic

Defense

1. Run your own private VPN on VPS

• Good for increasing the effort to exploit you• Bad because it’s cloud• Bad because all your traffic is directly attributed to you

2. Use a VPN service like PIA

• Good because it’s cheap and difficult (>0) to tell which is your traffic and which is someone else’s• Good because it doesn’t allow your ISP to see your traffic• Bad because the bigger the target the more likely you will “tasked”

3. Tor

• Good because anonymity• Bad because un-realistically slow