Thursday, March 28, 2024

Black Nurse attack: Will a single laptop bring down Servers/Routers

Black Nurse attack is a new-threat emerging on it’s horizon, it can be launched from a single laptop which is capable of bringing server/firewalls to their knees.

ICMP is an very commonly used protocol to identify live hosts, It is used by network devices like switches, Routers for sending error messages and operational information’s, for instance service is not available OR the host/server is reachable.You find the most detailed and types of ICMP code’s here.

Black Nurse attack mechanism

Most ICMP attacks based on Type 8 Code 0 also called ping flood attack. Blacknurse is based on ICMP with Type 3 Code 3 packets.We know that when a user has allowed ICMP Type 3 Code 3 to outside interfaces, the BlackNurse attack becomes highly effective even at low bandwidth.

black1

This attack will be more effective even with the Low bandwidth(15-18Mbit/s). When the attack in progress the users from the LAN network will not able to send/receive over the Internet. All the firewalls/router will recover will recover once the attack stops.

Different firewalls would have different implementation for handling this type of attack,this even applied to customers with large internet uplinks and large enterprise firewalls in place.

Evaluating the Risk

You can implement the test with WAN area of the firewall and at the time of attack try to surf some pages in and out of Internet.The tests also showed that a single attacking machine running hping3 could, on its own, produce enough ICMP type 3 code 3 packets to consume pretty much all the firewall’s resources.

hping3 –icmp -C 3 -K 3 -i u200 [target]

hping3 –icmp -C 3 -K 3 –flood [target]

Here -i u200 orders hping3 to send packets every 200microseconds and few minutes later they upped the packet rate, by using the “–flood” argument.

Detection/Affected products

  • Cisco ASA 5506, 5515, 5525 (default settings)
  • Cisco ASA 5550 (legacy) and 5515-X (latest generation)
  • Cisco Router 897 (can be mitigated)
  • SonicWall (misconfiguration can be changed and mitigated)
  • Some unverified Palo Alto
  • Zyxel NWA3560-N (wireless attack from LAN side)
  • Zyxel Zywall USG50

Impact

Based on the research, this vulnerability or misconfiguration of some firewalls is easy to misuse.Impact can be high for those that allow ICMP to the firewall’s outside interface. Having high bandwidth is no guarantee  that this DOS/DDOS attack will not work.Impact can be different from network to network depends on what the network is covering. It’s recommend to test your network.

Website

Latest articles

GoPlus’s Latest Report Highlights How Blockchain Communities Are Leveraging Critical API Security Data To Mitigate Web3 Threats

GoPlus Labs, the leading Web3 security infrastructure provider, has unveiled a groundbreaking report highlighting...

Wireshark 4.2.4 Released: What’s New!

Wireshark stands as the undisputed leader, offering unparalleled tools for troubleshooting, analysis, development, and...

Zoom Unveils AI-Powered All-In-One AI Work Workplace

Zoom has taken a monumental leap forward by introducing Zoom Workplace, an all-encompassing AI-powered...

iPhone Users Beware! Darcula Phishing Service Attacking Via iMessage

Phishing allows hackers to exploit human vulnerabilities and trick users into revealing sensitive information...

2 Chrome Zero-Days Exploited at Pwn2Own 2024: Patch Now

Google has announced a crucial update to its Chrome browser, addressing several vulnerabilities, including...

The Moon Malware Hacked 6,000 ASUS Routers in 72hours to Use for Proxy

Black Lotus Labs discovered a multi-year campaign by TheMoon malware targeting vulnerable routers and...
Guru baran
Guru baranhttps://gbhackers.com
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.

Mitigating Vulnerability Types & 0-day Threats

Mitigating Vulnerability & 0-day Threats

Alert Fatigue that helps no one as security teams need to triage 100s of vulnerabilities.

  • The problem of vulnerability fatigue today
  • Difference between CVSS-specific vulnerability vs risk-based vulnerability
  • Evaluating vulnerabilities based on the business impact/risk
  • Automation to reduce alert fatigue and enhance security posture significantly

Related Articles