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New Ripple20 Flaws Put Billions of Internet-Connected Devices at Risk of Hacking

New Ripple20 Flaws Put Billions of Internet-Connected Devices at Risk of Hacking

June 16, 2020Mohit Kumar
The Department of Homeland Security and CISA ICS-CERT today issued a critical security advisory warning about over a dozen newly discovered vulnerabilities affecting billions of Internet-connected devices manufactured by many vendors across the globe. Dubbed " Ripple20 ," the set of 19 vulnerabilities resides in a low-level TCP/IP software library developed by Treck, which, if weaponized, could let remote attackers gain complete control over targeted devices—without requiring any user interaction. According to Israeli cybersecurity company JSOF—who discovered these flaws—the affected devices are in use across various industries, ranging from home/consumer devices to medical, healthcare, data centers, enterprises, telecom, oil, gas, nuclear, transportation, and many others across critical infrastructure. "Just a few examples: data could be stolen off of a printer, an infusion pump behavior changed, or industrial control devices could be made to malfunction. An
New DNS Vulnerability Lets Attackers Launch Large-Scale DDoS Attacks

New DNS Vulnerability Lets Attackers Launch Large-Scale DDoS Attacks

May 20, 2020Ravie Lakshmanan
Israeli cybersecurity researchers have disclosed details about a new flaw impacting DNS protocol that can be exploited to launch amplified, large-scale distributed denial-of-service (DDoS) attacks to takedown targeted websites. Called NXNSAttack , the flaw hinges on the DNS delegation mechanism to force DNS resolvers to generate more DNS queries to authoritative servers of attacker's choice, potentially causing a botnet-scale disruption to online services. "We show that the number of DNS messages exchanged in a typical resolution process might be much higher in practice than what is expected in theory, mainly due to a proactive resolution of name-servers' IP addresses," the researchers said in the paper. "We show how this inefficiency becomes a bottleneck and might be used to mount a devastating attack against either or both, recursive resolvers and authoritative servers." Following responsible disclosure of NXNSAttack, several of the companies i
Firefox enables DNS-over-HTTPS by default (with Cloudflare) for all U.S. users

Firefox enables DNS-over-HTTPS by default (with Cloudflare) for all U.S. users

February 25, 2020Mohit Kumar
If you use the Firefox web browser, here's an important update that you need to be aware of. Starting today, Mozilla is activating the DNS-over-HTTPS security feature by default for all Firefox users in the U.S. by automatically changing their DNS server configuration in the settings. That means, from now onwards, Firefox will send all your DNS queries to the Cloudflare DNS servers instead of the default DNS servers set by your operating system, router, or network provider. As you may know, DNS-over-HTTPS (DoH) protocol performs DNS lookups — i.e., finding the server I.P. address of a certain domain name — over an encrypted connection to a DNS server rather than sending queries in the plaintext. This privacy-focused technology makes it harder for man-in-the-middle attackers, including your ISPs, to manipulate DNS queries, eavesdrop on your Internet connection, or learning what sites you visit. "This helps hide your browsing history from attackers on the network,
Google DNS Service (8.8.8.8) Now Supports DNS-over-TLS Security

Google DNS Service (8.8.8.8) Now Supports DNS-over-TLS Security

January 10, 2019Swati Khandelwal
Almost every activity on the Internet starts with a DNS query, a key function of the Internet that works as an Internet's directory where your device looks up for the server IP addresses after you enter a human-readable web address (e.g., thehackernews.com). Since DNS queries are sent in clear text over UDP or TCP without encryption, the information can reveal not only what websites an individual visits but is also vulnerable to spoofing attacks. To address these problems, Google announced Wednesday that its Public DNS (Domain Name System) service finally supports DNS-over-TLS security protocol, which means that the DNS queries and responses will be communicated over TLS-encrypted TCP connections. The DNS-over-TLS has been designed to make it harder for man-in-the-middle attackers to manipulate the DNS query or eavesdrop on your Internet connection. Launched over eight years ago, Google Public DNS, at IP addresses 8.8.8.8 and 8.8.4.4, is world's largest public Domai
How to Make Your Internet Faster with Privacy-Focused 1.1.1.1 DNS Service

How to Make Your Internet Faster with Privacy-Focused 1.1.1.1 DNS Service

April 02, 2018Mohit Kumar
Cloudflare, a well-known Internet performance and security company, announced the launch of 1.1.1.1 —world's fastest and privacy-focused secure DNS service that not only speeds up your internet connection but also makes it harder for ISPs to track your web history. Domain Name System (DNS) resolver, or recursive DNS server, is an essential part of the internet that matches up human-readable web addresses with their actual location on the internet, called IP addresses. For example, when you try to open a website, say thehackernews.com, your DNS looks up for the IP address linked to this domain name and load the site. Since the default DNS services provided by ISPs are often slow and insecure, most people rely on alternative DNS providers—such as OpenDNS (208.67.222.222), Comodo DNS (8.26.56.26) and Google (8.8.8.8), to speed up their Internet. But if you use Cloudflare new 1.1.1.1 DNS service , your computer/smartphone/tablet will start resolving domain names within a bla
New Rapidly-Growing IoT Botnet Threatens to Take Down the Internet

New Rapidly-Growing IoT Botnet Threatens to Take Down the Internet

October 21, 2017Wang Wei
Just a year after Mirai —biggest IoT-based malware that caused vast Internet outages by launching massive DDoS attacks—completed its first anniversary, security researchers are now warning of a brand new rapidly growing IoT botnet. Dubbed ' IoT_reaper ,' first spotted in September by researchers at firm Qihoo 360, the new malware no longer depends on cracking weak passwords; instead, it exploits vulnerabilities in various IoT devices and enslaves them into a botnet network. IoT_reaper malware currently includes exploits for nine previously disclosed vulnerabilities in IoT devices from following manufactures: Dlink (routers) Netgear (routers) Linksys (routers) Goahead (cameras) JAWS (cameras) AVTECH (cameras) Vacron (NVR) Researchers believe IoT_reaper malware has already infected nearly two million devices and growing continuously at an extraordinary rate of 10,000 new devices per day. This is extremely worrying because it took only 100,000 infected devices
Critical glibc Flaw Puts Linux Machines and Apps at Risk (Patch Immediately)

Critical glibc Flaw Puts Linux Machines and Apps at Risk (Patch Immediately)

February 17, 2016Swati Khandelwal
A highly critical vulnerability has been uncovered in the GNU C Library (glibc) , a key component of most Linux distributions, that leaves nearly all Linux machines, thousands of apps and electronic devices vulnerable to hackers that can take full control over them. Just clicking on a link or connecting to a server can result in remote code execution (RCE), allowing hackers to steal credentials, spy on users, seize control of computers, and many more. The vulnerability is similar to the last year's  GHOST vulnerability (CVE-2015-0235) that left countless machines vulnerable to remote code execution (RCE) attacks , representing a major Internet threat. GNU C Library (glibc) is a collection of open source code that powers thousands of standalone apps and most Linux distributions, including those distributed to routers and other types of hardware. The recent flaw, which is indexed as CVE-2015-7547 , is a stack-based buffer overflow vulnerability in glibc's D
Google Public DNS Server Spoofed for SNMP based DDoS Attack

Google Public DNS Server Spoofed for SNMP based DDoS Attack

September 16, 2014Wang Wei
The Distributed Denial of Service ( DDoS ) attack is becoming more sophisticated and complex, and, according to security experts , the next DDoS vector to be concerned about is SNMP (Simple Network Management Protocol) amplification attacks. Yesterday afternoon, the SANS Internet Storm Center reported SNMP scans spoofed from Google's public recursive DNS server searching for vulnerable routers and other devices that support the protocol with DDoS traffic and are opened to the public Internet. " We are receiving some reports about SNMP scans that claim to originate from 8.8.8.8 (Google's public recursive DNS server), " wrote Johannes Ullrich, dean of research of the SANS Technology Institute and head of the Internet Storm Center. " This is likely part of an attempt to launch a DDoS against Google by using SNMP as an amplifier/reflector. " Simple Network Management Protocol (SNMP) is a UDP-based protocol designed to allow the monitoring of network-
Millions of Vulnerable Routers aiding Massive DNS Amplification DDoS Attacks

Millions of Vulnerable Routers aiding Massive DNS Amplification DDoS Attacks

April 03, 2014Swati Khandelwal
The Distributed Denial of Service (DDoS) attack is becoming more sophisticated and complex with the increase in the skills of attackers and so, has become one of favorite weapon for the cyber criminals to temporarily suspend or crash the services of a host connected to the Internet and till now nearly every big site had been a victim of this attack. Since 2013, Hackers have adopted new tactics to boost the sizes of Distributed Denial of Service ( DDoS ) attack known as ' Amplification Attack ', leveraging the weakness in the UDP protocols. One of the commonly used by hacker is (Domain Name System) DNS Reflection Denial of Service (DrDoS). WHAT IS DrDoS ATTACK? The DNS Reflection Denial of Service (DrDoS) technique exploits security weaknesses in the Domain Name System (DNS) Internet protocol. Using Internet protocol spoofing, the source address is set to that of the targeted victim, which means all the replies will go to the target and the target of the attack receives re
Google Public DNS Server Traffic Hijacked

Google Public DNS Server Traffic Hijacked

March 17, 2014Mohit Kumar
The Internet is becoming a dangerous place day-by-day and especially for those innocent web users who rely on 3rd party services. The latest bad news is that the World's largest and most widely used Google's free public DNS (Domain name system) resolvers  raised   security red flags yesterday. DNS is the master address list for the Internet, which translates IP addresses into human readable form and vice versa. According to Internet monitoring firm BGPmon , Google's DNS server 8.8.8.8 /32 was hijacked yesterday for 22 minutes. The Google's DNS server handles around 150 billion queries a day and during the 22 minutes of hijacking, millions of Internet users, including Financial institutions , Governments were redirected to BT's (British multinational telecommunications services company) Latin America division in Venezuela and Brazil. It is suspected that Hackers exploited a well-known  vulnerability in the so-called Border Gateway Protocol ( BGP) , which
Massive 167Gbps DDoS attacks against Banking and Financial Institutions

Massive 167Gbps DDoS attacks against Banking and Financial Institutions

May 31, 2013Mohit Kumar
DDoS attackers attempted to bring down an Banking services earlier this week using one of the largest Distributed denial of service attack using DNS reflection technique. Prolexic, the global leader in Distributed Denial of Service (DDoS) protection services, announced  that it has successfully mitigated the largest DNS reflection attack ever recorded, which peaked at 167 Gigabits per second (Gbps). The company did not name the target of the digital assault. DNS-reflection was the attack method used in Operation Stophaus , an attack waged in March by The Spamhaus Project, a Geneva-based not-for-profit organization dedicated to fighting Internet spam . When Spamhaus was assaulted by a vast 300Gbps peak DNS reflection attack, it engaged the help of a content delivery network (CDN) called CloudFlare to help defend itself. The DNS Reflection Denial of Service (DrDoS) technique exploits security weaknesses in the Domain Name System (DNS) Internet protocol. Using Internet protocol spoof
Millions of WordPress sites exploitable for DDoS Attacks using Pingback mechanism

Millions of WordPress sites exploitable for DDoS Attacks using Pingback mechanism

May 01, 2013Mohit Kumar
Distributed Denial of Service attacks have increased in scale, intensity and frequency. The wide range of motives for these attacks political , criminal, or social makes every merchant or organization with an online presence a potential target. Over the weekend Incapsula mitigated a unique DDoS attack against a large gaming website, in which they have discovered a DDoS attack using thousands of legitimate WordPress blogs without the need for them to be compromised. Incapsula released the list of approximately 2,500 WordPress sites from where the attack was originated, including some very large sites like Trendmicro.com, Gizmodo.it and Zendesk.com . In a recent report , we posted about another method for DDoS attacks using DNS amplification , where a DNS request is made to an open DNS resolver with the source IP address forged so that it is the IP address of the targeted site to which the response is thus sent, but this new method uses HTTP rather than DNS. The
Who Needs a Botnet when you have a 4 Gbps DDoS Cannon?

Who Needs a Botnet when you have a 4 Gbps DDoS Cannon?

April 24, 2013Mohit Kumar
In recent months the DDoS world has shifted from complex small scale Botnet attacks to much larger network based DDoS attacks , perpetrated largely by hijacked web servers. How many of these hijacked servers are out there remains to be seen. However, Incapsula recently got a very good idea of just how large these DDoS cannons are getting. Last Saturday Incapsula mitigated a rather small, 4Gbps DDoS attack, but this time it had a different pattern that attracted our attention. At first sight the attack seemed rather simple, generating 8 million DNS queries per second, to many domains, from spoofed IP addresses (using real domain name servers' IPs). But this time it included a hint about where it was coming from: all that traffic was coming from the same source. Probably on the same network, maybe even the same device. Tracing it to a single Source - TTL Giveaway Incapsula were able to trace the attack to a single source because this time the attackers slipped-u
World's biggest DDoS attack that Almost Broke the Internet

World's biggest DDoS attack that Almost Broke the Internet

March 29, 2013Mohit Kumar
The last week has seen probably the largest distributed denial-of-service (DDoS) attack ever. A massive 300Gbps was thrown against Internet blacklist maintainer Spamhaus' website but the anti-spam organisation , CloudFlare was able to recover from the attack and get its core services back up and running.  Spamhaus, a group based in both London and Geneva, is a non-profit organisation that aims to help email providers filter out spam and other unwanted content. Spamhaus is pretty resilient, as its own network is distributed across many countries, but the attack was still enough to knock its site offline on March 18. Five national cyber-police-forces are investigating the attacks.  A group calling itself STOPhaus,  an alliance of hactivists and cyber criminals is believed to responsible for bombarding Spamhaus with up to 300Gbps. The attacks on Spamhaus illustrate a larger problem with the vulnerability of systems fundamental to the architecture of the Internet, the D
CVE-2012-2808 : Android 4.0.4 DNS poisoning vulnerability Exposed

CVE-2012-2808 : Android 4.0.4 DNS poisoning vulnerability Exposed

July 24, 2012Mohit Kumar
Android's DNS resolver is vulnerable to DNS poisoning due to weak randomness in its implementation. Researchers Roee Hay & Roi Saltzman from IBM Application Security Research Group demonstrate that how an attacker can successfully guess the nonce of the DNS request with a probability thatis su cient for a feasible attack. Android version 4.0.4 and below are Vulnerable to this bug. Weakness in its pseudo-random number generator (PRNG), which makes DNS poisoning attacks feasible. DNS poisoning attacks may endanger the integrity and con dentiality of the attacked system. For example, in Android, the Browser app can be attacked in order to steal the victim's cookies of a domain of the attacker's choice. If the attacker manages to lure the victim to browse to a web page controlled by him/her, the attacker can use JavaScript, to start resolving non-existing sub-domains. Upon success, a sub-domain points to the attacker's IP, which enables the latter to steal wild card
Patches Released for BIND Denial-of-service Vulnerability

Patches Released for BIND Denial-of-service Vulnerability

November 17, 2011Mohit Kumar
Patches Released for BIND Denial-of-service Vulnerability There's a new vulnerability in the popular BIND name server software that is causing various versions of the application to crash unexpectedly after logging a certain kind of error. The Internet Systems Consortium (ISC), an organization that maintains several software products critical for Internet infrastructure, has released a patch for an actively exploited denial-of-service vulnerability in the widely used BIND DNS server. The internet Systems Consortium (ISC) have described the problem as follows: An as-yet unidentified network event caused BIND 9 resolvers to cache an invalid record, subsequent queries for which could crash the resolvers with an assertion failure... Affected servers crashed after logging an error in query.c with the following message: "INSIST(! dns_rdataset_isassociated(sigrdataset)) More details are available in their advisory . As of this posting, ISC had not revealed the underlying problem,
Knock v1.5 - Subdomain Scanner , allows to bypass wildcard

Knock v1.5 - Subdomain Scanner , allows to bypass wildcard

August 24, 2011Mohit Kumar
Knock v1.5  - Subdomain Scanner , allows to bypass wildcard Knock is a python script, written by Gianni 'guelfoweb' Amato, designed to enumerate subdomains on a target domain through a wordlist. This program is self contained, doesn't need to be installed in any particular location. All it needs is a recent version of Python 2.xOnly for use the Zone Transfer option (-zt) you must install the module dnspython, otherwise you can do without. If the name server allows zone transfers to occur, all the DNS names and IP addresses hosted by the name server will be returned in human-readable ASCII text. Usage $ python knock.py <option> <url> Rapid Scan Scanning with internal wordlist: $ python knock.py <url> Scanning with external wordlist: $ python knock.py <url> <wordlist> Options -zt Zone Transfer discovery: $ python knock.py -zt <url> -dns Dns resolver: $ python knock.py -dns <url> -wc Wildcard testing: $ python knock.py
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