Saturday, July 13, 2024

DUHK Attack allows Hackers to Recover Encryption Keys and Decrypt Communications Passing Over VPN

DUHK attack targets the old vulnerability that resides in the pseudorandom number generator called ANSI X9.31. It is an algorithm widely used to generate cryptographic keys that secure VPN connections and web browsing sessions.

ANSI X9.31 PRNG is a pseudorandom number generator algorithm design that was incorporated into different structures cryptographic standards and listed as recommended RNG for FIPS certification for decades.

DUHK attack allows hackers to recover encryption keys and to decrypt the encrypted web traffic.This vulnerability hits devices utilizing ANSI X9.31 Random Number Generator (RNG) in combination with a hard-coded seed key. This cryptographic attack followed by Factorization Attack and KRACK Attack.

Researchers wrote We performed a systematic study of publicly available FIPS 140-2 certifications for hundreds of products that implemented the ANSI X9.31 random number generator, and found twelve whose certification documents use of static hard-coded keys in the source code, leaving them vulnerable to an attacker who can learn this key from the source code or binary.

DUHK was developed by researchers at the University of Pennsylvania and Johns Hopkins University: Shaanan Cohney, Nadia Heninger, and Matthew D. Green.

Devices Vulnerable to DUHK Attack

For demonstration, researchers developed a full passive decryption attack against FortiGate VPN gateway products using FortiOS version 4 and they were able to recover the random number generator state for 21% of HTTPS hosts serving a default Fortinet product certificate.

Researchers used ZMap to perform Internet-wide scans on port 443 for HTTPS and port 500 to measure the population of vulnerable Fortinet devices and they found 23,000 devices are running a vulnerable version of FortiOS.

FortiGate devices with FortiOS 4.3.0 to FortiOS 4.3.18 are vulnerable to DUHK attacks and Fortigate fixed it by implementing CTR_DRBG from FortiOS 4.3.19, 5.0.(CVE-2016-8492).

Researchers provided a list of the Hardware and software products that are vulnerable to DUHK.

AM I Vulnerable?

X9.31 RNG was removed FIPS list of approved RNGs in 2016. If your product was certified after 2016 then you are not vulnerable.

The x9.31 vulnerability is symmetric, and any implementation that stores a fixed secret key in code or hardware is vulnerable to passive exploitation by an attacker who can recover the key through reverse engineering.

Updating software regularly is a good practice to protect you against flaws. More details on DUHK attack found in the dedicated page or the blog post by Matthew Green.


Latest articles

mSpy Data Breach: Millions of Customers’ Data Exposed

mSpy, a widely used phone spyware application, has suffered a significant data breach, exposing...

Advance Auto Parts Cyber Attack: Over 2 Million Users Data Exposed

RALEIGH, NC—Advance Stores Company, Incorporated, a prominent commercial entity in the automotive industry, has...

Hackers Using ClickFix Social Engineering Tactics to Deploy Malware

Cybersecurity researchers at McAfee Labs have uncovered a sophisticated new method of malware delivery,...

Coyote Banking Trojan Attacking Windows Users To Steal Login Details

Hackers use Banking Trojans to steal sensitive financial information. These Trojans can also intercept...

Hackers Created 700+ Fake Domains to Sell Olympic Games Tickets

As the world eagerly anticipates the Olympic Games Paris 2024, a cybersecurity threat has...

Japanese Space Agency Spotted zero-day via Microsoft 365 Services

The Japan Aerospace Exploration Agency (JAXA) has revealed details of a cybersecurity incident that...

Top 10 Active Directory Management Tools – 2024

Active Directory Management Tools are essential for IT administrators to manage and secure Active...
Guru baran
Guru baran
Gurubaran is a co-founder of Cyber Security News and GBHackers On Security. He has 10+ years of experience as a Security Consultant, Editor, and Analyst in cybersecurity, technology, and communications.

Free Webinar

Low Rate DDoS Attack

9 of 10 sites on the AppTrana network have faced a DDoS attack in the last 30 days.
Some DDoS attacks could readily be blocked by rate-limiting, IP reputation checks and other basic mitigation methods.
More than 50% of the DDoS attacks are employing botnets to send slow DDoS attacks where millions of IPs are being employed to send one or two requests per minute..
Key takeaways include:

  • The mechanics of a low-DDoS attack
  • Fundamentals of behavioural AI and rate-limiting
  • Surgical mitigation actions to minimize false positives
  • Role of managed services in DDoS monitoring

Related Articles