Category Archives: Survival tips

US Gas Pipelines Hit by Cyber-Attack

15 April 2018

The report “US Gas Pipelines Hit by Cyber-Attack” (1), published on April 13, 2018 in Infosecurity Magazine, sounds more dramatic than it actually is. The attackers compromised a system for “electronic data interchange” (EDI) to some of the largest US energy providers. No impact on critical infrastructures, at least until now.

Bloomberg Technology (2) reports that at least four US pipeline companies were affected by the attack.

What surprised me was that Jim Guinn, managing director and global cyber security leader for energy, utilities, chemicals and mining at Accenture Plc, said (2):

 

“There is absolutely nothing of intrinsic value for someone to infiltrate the EDI other than to navigate a network to do something more malicious. All bad actors are looking for a way to get into the museum to go steal the Van Gogh painting.”

I cannot support this. The EDI system contains the access details to the systems used in the customer networks for data exchange. These details are the free admission ticket to the customer networks for the cyber-criminals.

Thus, it is very important that at least the access data to customer systems are changed directly after an attack is detected. In addition, the customers should check their networks for suspicious data transfers and indicators for lateral movement.

Have a good weekend.


1. Muncaster P. US Gas Pipelines Targeted in Cyber-Attack [Internet]. Infosecurity Magazine. 2018 [cited 2018 Apr 13]. Available from: https://www.infosecurity-magazine.com:443/news/us-gas-pipelines-hit-by-cyberattack/

2. Malik NS, Collins R, Vamburkar M. Cyberattack Pings Data Systems of At Least Four Gas Networks. Bloomberg.com [Internet]. 2018 Apr 3 [cited 2018 Apr 15]; Available from: https://www.bloomberg.com/news/articles/2018-04-03/day-after-cyber-attack-a-third-gas-pipeline-data-system-shuts

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RYZENFALL, MASTERKEY, FALLOUT, CHIMERA – Don’t Panic!

3 April 2018

CTS-Labs publication (1) of new branded security flaws in AMD’s latest Ryzen and EPYC processors attracted much media attention.

Much Ado About Nothing

Much Ado About Nothing. Made with WortArt.com.

Two facts on RYZENFALL, MASTERKEY, FALLOUT and CHIMERA:

  • In all cases the attacker requires administrative access to exploit the processor flaws.
  • For exploitation of MASTERKEY the attacker needs to re-flash the bios.

For a good overview see post ‘AMD Flaws’ (2) in the Trail of Bits blog.

To put it succinctly:: An attacker managed to fully compromise a system based on an AMD Ryzen or EPYC processor and to stay undetected. Then he starts exploiting Masterkey, flashes the BIOS and reboots the system. As a result he gets directly detected.

That makes no sense. Once I fully compromised a system I have plenty opportunities to run a deep dive into the victim’s network and, to stay undetected. The risk of getting detected when exploiting e.g. MASTERKEY is just too high.

The world of threat actors can be divided in two classes: Non-Nation State Actors and Nation State Actors. In particular MASTERKEY fits perfectly in the cyber weapon arsenal of the latter because only they have the resources to compromise the processors where it is most convenient, in the supply chain.

I don’t like branded vulnerabilities because they keep us from dealing with really important security issues.

Have a great week!


  1. CTS-Labs. Severe Security Advisory on AMD Processors [Internet]. AMDFLAWS. 2018 [cited 2018 Apr 3]. Available from: https://safefirmware.com/amdflaws_whitepaper.pdf

  2. Guido D. “AMD Flaws” Technical Summary [Internet]. Trail of Bits Blog. 2018 [cited 2018 Apr 3]. Available from: https://blog.trailofbits.com/2018/03/15/amd-flaws-technical-summary/

Triton: Dangerous and Puzzling – Part III

18 March 2018

The reports published on Triton so far give no hint on how the attack was started. With Occam’s razor in mind I concluded in part II of this post series that it is very likely, that the attacker compromised the Engineering Service Providers (ESP) network and the systems used for developing the SIS software. Since the next software update is sure to come, it is only a matter of time until the SIS installation in the production network gets compromised.

In this part I will talk about how to prevent and protect against such attacks.

Part III: Prevention and Protection

To protect against such kind of attacks data integrity must be ensured across the entire supply chain.

Ensure Integrity Across the Supply Chain

Ensure Integrity Across the Supply Chain

Engineering Service Provider’s responsibilities

Build: The ESP must make sure that the project data and software cannot be compromised in his facilities during software design and build.

Transfer: The ESP must secure the data against manipulation during transport.

Plant Operator’s responsibilities

Validate: After handover, the operator must check that the software and project data fulfil only the intended functions, before the SIS or DCS is updated. This must be governed by a Standard Operating Procedures (SOP) with formal approvals.

Install: The operator must follow a SOP for secure update of SIS and DCS software.

In the following section I will give some best practice to achieve data integrity across the supply chain. Anti-malware solutions are not listed because they are industry standard. Nevertheless, it is important to note that in Triton like cases pattern based anti-malware solutions will not prevent or protect against the attack. Pattern based anti-malware solutions protect only against malware “in the wild”. That’s not the case here, thus we have to apply other means to ensure integrity.


Development network

  • Perform all project work in an isolated Development Network (D-NET) with a Development DMZ (D-DMZ).
  • Control remote access to the D-DMZ through a user proxy to allow access for authorized staff only. Two Factor Authentication is mandatory for access to the D-DMZ.
  • For remote user access to the D-NET use a jump station in the D-DMZ.
  • Terminate all connections from the Office Network to the D-NET in the D-DMZ.
  • Terminate all connections from the D-NET in the D-DMZ.
  • If an SIS or DCS is operated in the D-NET, it should be placed in an isolated in a network  zone (D-SIS) in the D-NET. Allow only incoming connections from the engineering station to the SIS or DCS. Terminate all outgoing connections from the D-SIS in the D-NET.

Data exchange

  • For data exchange with the Office network allow only outgoing connections from the D-DMZ to dedicated systems/ports in the Office network.
  • Don’t use the SMB protocol for exchange of data between the office network and the D-DMZ and D-NET.
  • Implement Network Access Control (NAC) in the D-DMZ and D-NET to block connections of untrusted devices.
  • Never connect mobile workstations used in the D-NET or D-DMZ to other networks and vice versa. Once such a workstation was connected to a network outside the D-NET or D-DMZ it is potentially compromised.

System hardening

  • Block all USB disk devices in the D-NET.
  • Block all internet access and e-mail in the D-DMZ and D-NET.
  • Lock down all workstations and servers in the D-NET and D-DMZ.
  • Perform regular integrity checks on all systems in the D-NET and D-DMZ.

Software development best practice

  • Set up software version control for all development work.
  • If contractually possible, handover only sources, makefiles and checksums to the operator.

  • Secure network transfer is the method of choice. Bundle all sources in an encrypted archive. Send the encryption key in a secure e-mail to the operator.
  • If transfer by USB devices is required use only USB devices with AES hardware encryption and key pad. Run a secure before the new software is copied.

  • Extract the software to a trusted development system in an isolated network zone of the operators network.
  • Validate the checksums of the sources and makefiles against the supplied checksum details.
  • Build the software.
  • Install the software on a test system and verify that only the intended functions are implemented.

  • Use a secure transfer method to move the new software and project data to the SIS or DCS  network.
  • Install the software with regards to the corresponding SOP.

Have a great week.

How to defeat antivirus evasion and privilege escalation techniques

4 February 2018

Last weekend I read two very informative posts on Antivirus Evasion by Mattia Campagnano. But part 2 [1] puzzled me somewhat.

“Following up to my previous post Tips for an Information Security Analyst/Pentester career – Ep. 43: AV Evasion (pt. 1), we’re going now to perform the same attack on a genuine Windows 10 machine, where all latest updates have been installed.”

For a moment I thought ‘a security professional mistakes compliance for security’ because ‘fully patched’ means not that the system is resilient against cyber-attacks. But both posts show that even the most secure Windows ever is vulnerable against privilege escalation and AV evasion if the basic configuration is not changed and fundamental elements of cyber hygiene are missing.

Why are such attacks successful?

First, the user was logged in with permanent administrative privileges. This makes life easy for attackers and fosters lateral movement.

Revoking permanent administrative privileges on workstations and servers must be a basic element of any cyber security program. Under normal conditions, standard users should not have any administrative privileges for their devices at all. If needed, they can be temporarily granted through User Account Control (UAC).

Second, UAC was not set to the highest level “Always notify me”. Unfortunately this is the standard setting after a fresh installation of Windows. With this, privilege escalation is possible without user notification. If configured properly, UAC will notify the user even if he works with administrative privileges.

The BypassUAC method in the meterpreter attack framework will fail, if UAC is set to the highest level. The following excerpt of the code [2] makes this clear

case get_uac_level
 when UAC_PROMPT_CREDS_IF_SECURE_DESKTOP,
      UAC_PROMPT_CONSENT_IF_SECURE_DESKTOP,
      UAC_PROMPT_CREDS, UAC_PROMPT_CONSENT
 fail_with(Failure::NotVulnerable,
  "UAC is set to 'Always Notify'. This module does not bypass this setting, exiting..."
 )
 when UAC_DEFAULT
    print_good('UAC is set to Default')
    print_good('BypassUAC can bypass this setting, continuing...')
 when UAC_NO_PROMPT
    print_warning('UAC set to DoNotPrompt - using ShellExecute "runas" method instead')
    shell_execute_exe
  return
end

Standards like the DISA STIG for Windows 10 [3] activate all UAC features to make life for the attackers as difficult as possible. From my point of view, the STIGs should be considered also in industry to create workplaces resilient against cyber-attacks. And Microsoft should raise the Windows default for UAC to “Always notify me” for all versions. If a user wants to reduce the security level, he should do this on his own responsibility.

Besides the secure configuration of IT systems and cyber hygiene is user awareness training the third essential pillar of a security program. Users and help desk staff must take proper actions if their system unexpectedly enters the secure desktop and asks for permissions of an action they never asked.

Have a good weekend.


  1. Campagnano, M. Tips for an Information Security Analyst/Pentester career – Ep. 44: AV Evasion (pt 2). The S@vvy_Geek Tips Tech Blog
  2. Rapid7 bypassuac_vbs.rb  Metasploit Framework. (Accessed: 3rd February 2018)
  3. Windows 10 Security Technical Implementation Guide. STIG Viewer | Unified Compliance Framework® Available at: https://www.stigviewer.com/stig/windows_10/. (Accessed: 3rd February 2018)
  4. Campagnano, M. Tips for an Information Security Analyst/Pentester career – Ep. 43: AV Evasion (pt.1). The S@vvy_Geek Tips Tech Blog

Some thoughts on “Identity is the new perimeter”

28 January 2018

With the increasing adoption of cloud services, the traditional perimeter security approach becomes less and less effective. The on-premise security layer, which protects users against cyber-attacks, is just no longer existent if users have direct access to a company’s cloud services from any location, at any time and, in the best case, from any device.

The four “A”s, Authentication, Authorization, Administration and Audit, become more and more important in a [hybrid] cloud based working environment.

“When identity and access management (IAM) works well, it means the right people have the right access to the right resources when they need them with appropriate governance in place from wherever the data or application is needed.” [1]

The magic word is “right”: With IAM we control the access of well-known groups of people to well-known resources. Unfortunately, cyber attackers do often not belong to these groups.

NIST NVD Statistics: Privileges Required

From the NIST NVD we learn, that 67% of the vulnerabilities published in 2017 need no privileges for exploitation.

Privileges None means: “The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.” [2]

This holds e.g. for remote code execution (RCE) vulnerabilities. An RCE allows an attacker to get full control of the victim’s computer or service, in the worst case with administrative privileges. With this, the entire new perimeter is bypassed. For an RCE example see CVE-2017-11459. [3]

Identity becomes an important part of a new perimeter but can never replace the perimeter.

NIST NVD 2017 Statistics: User Interaction Required

The NIST NVD data give another important insight for shaping a company’s security strategy: In 41% (5958) of 14647 vulnerabilities the user must interact with the attacker for their exploitation.

This means that well-made user awareness training can prevent lots of cyber-attacks.

Have a great week.


[1] AusCERT 2017 – Identity is the new perimeter
Anthony Caruana, 05/30/2017, CSO Online
https://www.cso.com.au/article/619970/auscert-2017-identity-new-perimeter/
Last seen: 01/28/2018

[2] Common Vulnerability Scoring System v3.0: Specification Document
https://www.first.org/cvss/specification-document
Last seen: 01/28/2018

[3] CVE-2017-11459
https://nvd.nist.gov/vuln/detail/CVE-2017-11459
Last seen: 01/28/2018

Intel AMT flaw lets attackers take control of laptops in 30 seconds

20 January 2018

Intel’s Active Management Technology (AMT) offers impressive management features to company IT shops:

  • Asset discovery
  • Out-of-band management functions to fix systems even if the OS went down
  • Contain the impact of malware

As any other software, AMT has configuration issues and vulnerabilities. For example, in 2015 default factory settings could be leveraged by an attacker to gain full control over devices from the network. Last year, four vulnerabilities were published in the NVD Database.

The latest configuration issue published on January 12, 2018 by F-Secure researchers allows attackers with physical access to compromise systems easily:

Just press CTRL-P during boot and log into Intel Management Engine BIOS Extension (MEBx) using the default password “admin”. With this, an attacker can reconfigure the system to allow for example remote access once the system is booted and left unattended.

This type of attack is called Evil Maid Attack. It is used especially by cyber criminals and nation state actors to compromise systems.

Although Intel made recommendations to mitigate this issue, the F-Secure report makes clear, that the OEM’s did not implement them and that the system managers did not change the AMT password on delivery to the users.

With this, we have no choice but to set individual AMT and BIOS passwords on all laptops and mobile devices with AMT enabled. This is going to be a hard job in companies with some thousand devices.

A risk based approach makes sense: Start with the top management and employees which have access to business-critical information.

Have a great weekend.

Spectre and Meltdown – No need to enter Panic Mode

7 January 2018

Spectre Icon

Spectre

When I read about Meltdown and Spectre in the Reuters Technology News early on Wednesday morning I digged directly somewhat deeper to find details about the access vectors and severity. From a quick view of the published material I concluded that these vulnerabilities were only locally exploitable and would have medium to high impact. No need to panic.

Media coverage was very high the next morning. Even the German local radio stations brought details about Spectre and Meltdown in the news, although there was no ground for public panic.

The following table shows the Meltdown and Spectre vulnerability details:

Meltdown and Spectre Vulnerability Details, CVSS V3 Metrics

Meltdown and Spectre Vulnerability Details, CVSS V3 Metrics

Sources: [1] NIST NVD, [2] RedHat Customer Portal[3] NIST NVD
Abbreviation list: AV: Access Vector, AC: Access Complexity, PR: Privileges Required, UI: User Interaction, C: Confidentiality, I: Integrity, A: Avaliability

To exploit these vulnerabilities an attacker must have either local access to a system on your network (Access Vector Local) or access to your local network (Access Vector Adjacent Network).

But why should an attacker, who got access to a system on your network, exploit e.g. Meltdown to extract passwords from the memory of a process? The access complexity is high; thus, the likelihood of early detection goes up.

We can expect that cyber criminals don’t behave irrationally. They choose the attack method with low chance of detection. And recent publications suggest this:

According to the Ponemon 2017 Cost of Data Breach Study the Mean Time to Identify (MTTI) a data breach in 2016 was 191 days, down from 201 days in 2015. If cyber criminals would behave irrationally, the MTTI would be much shorter.

Thus, there is no need for panic. Just apply the latest patches and check the performance of critical systems.

Have a great week.