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Cisco Issues Patches For 2 High-Severity IOS XR Flaws Under Active Attacks

Cisco Issues Patches For 2 High-Severity IOS XR Flaws Under Active Attacks
September 30, 2020Wang Wei
Cisco yesterday released security patches for two high-severity vulnerabilities affecting its IOS XR software that were found exploited in the wild a month ago. Tracked as CVE-2020-3566 and CVE-2020-3569 , details for both zero-day unauthenticated DoS vulnerabilities were made public by Cisco late last month when the company found hackers actively exploiting Cisco IOS XR Software that is installed on a range of Cisco's carrier-grade and data center routers. Both DoS vulnerabilities resided in Cisco IOS XR Software's Distance Vector Multicast Routing Protocol (DVMRP) feature and existed due to incorrect implementation of queue management for Internet Group Management Protocol (IGMP) packets on affected devices. IGMP is a communication protocol typically used by hosts and adjacent routers to efficiently use resources for multicasting applications when supporting streaming content such as online video streaming and gaming. "These vulnerabilities affect any Cisco device th

Google Researcher Reported 3 Flaws in Apache Web Server Software

Google Researcher Reported 3 Flaws in Apache Web Server Software
August 24, 2020Ravie Lakshmanan
If your web-server runs on Apache, you should immediately install the latest available version of the server application to prevent hackers from taking unauthorized control over it. Apache recently fixed multiple vulnerabilities in its web server software that could have potentially led to the execution of arbitrary code and, in specific scenarios, even could allow attackers to cause a crash and denial of service. The flaws, tracked as CVE-2020-9490, CVE-2020-11984, CVE-2020-11993, were uncovered by Felix Wilhelm of Google Project Zero, and have since been addressed by the Apache Foundation in the latest version of the software ( 2.4.46 ). The first of the three issues involve a possible remote code execution vulnerability due to a buffer overflow with the "mod_uwsgi" module (CVE-2020-11984), potentially allowing an adversary to view, change, or delete sensitive data depending on the privileges associated with an application running on the server. "[A] Malici

Citrix Issues Critical Patches for 11 New Flaws Affecting Multiple Products

Citrix Issues Critical Patches for 11 New Flaws Affecting Multiple Products
July 08, 2020Ravie Lakshmanan
Citrix yesterday issued new security patches for as many as 11 security flaws that affect its Citrix Application Delivery Controller (ADC), Gateway, and SD-WAN WAN Optimization edition (WANOP) networking products. Successful exploitation of these critical flaws could let unauthenticated attackers perform code injection, information disclosure, and even denial-of-service attacks against the gateway or the authentication virtual servers . Citrix confirmed that the aforementioned issues do not impact other virtual servers, such as load balancing and content switching virtual servers. Among the affected Citrix SD-WAN WANOP appliances include models 4000-WO, 4100-WO, 5000-WO, and 5100-WO. The networking vendor also reiterated that these vulnerabilities were not connected to a previously fixed zero-day NetScaler flaw (tagged as CVE-2019-19781 ) that allowed bad actors to perform arbitrary code execution even without proper authentication. It also said there's no evidence

New Critical Exim Flaw Exposes Email Servers to Remote Attacks — Patch Released

New Critical Exim Flaw Exposes Email Servers to Remote Attacks — Patch Released
September 30, 2019Swati Khandelwal
A critical security vulnerability has been discovered and fixed in the popular open-source Exim email server software, which could allow a remote attacker to simply crash or potentially execute malicious code on targeted servers. Exim maintainers today released an urgent security update— Exim version 4.92.3 —after publishing an early warning two days ago, giving system administrators an early head-up on its upcoming security patches that affect all versions of the email server software from 4.92 up to and including then-latest version 4.92.2. Exim is a widely used, open source mail transfer agent (MTA) developed for Unix-like operating systems like Linux, Mac OSX or Solaris, which runs almost 60 percent of the Internet's email servers today for routing, delivering and receiving email messages. This is the second time in this month when the Exim maintainers have released an urgent security update. Earlier this month, the team patched a critical remote code execution flaw (

8 New HTTP/2 Implementation Flaws Expose Websites to DoS Attacks

8 New HTTP/2 Implementation Flaws Expose Websites to DoS Attacks
August 14, 2019Mohit Kumar
Various implementations of HTTP/2 , the latest version of the HTTP network protocol, have been found vulnerable to multiple security vulnerabilities affecting the most popular web server software, including Apache, Microsoft's IIS, and NGINX. Launched in May 2015, HTTP/2 has been designed for better security and improved online experience by speeding up page loads. Today, over hundreds of millions of websites, or some 40 percent of all the sites on the Internet, are running using HTTP/2 protocol. A total of eight high-severity HTTP/2 vulnerabilities , seven discovered by Jonathan Looney of Netflix and one by Piotr Sikora of Google, exist due to resource exhaustion when handling malicious input, allowing a client to overload server's queue management code. The vulnerabilities can be exploited to launch Denial of Service (DoS) attacks against millions of online services and websites that are running on a web server with the vulnerable implementation of HTTP/2 , knocking

Update Samba Servers Immediately to Patch Password Reset and DoS Vulnerabilities

Update Samba Servers Immediately to Patch Password Reset and DoS Vulnerabilities
March 13, 2018Mohit Kumar
Samba maintainers have just released new versions of their networking software to patch two critical vulnerabilities that could allow unprivileged remote attackers to launch DoS attacks against servers and change any other users' passwords, including admin's. Samba is open-source software (re-implementation of SMB networking protocol) that runs on the majority of operating systems available today, including Windows, Linux, UNIX, IBM System 390, and OpenVMS. Samba allows non-Windows operating systems, like GNU/Linux or Mac OS X, to share network shared folders, files, and printers with Windows operating system. The denial of service vulnerability, assigned CVE-2018-1050 , affects all versions of Samba from 4.0.0 onwards and could be exploited "when the RPC spoolss service is configured to be run as an external daemon." "Missing input sanitization checks on some of the input parameters to spoolss RPC calls could cause the print spooler service to crash.

Memcached Servers Abused for Massive Amplification DDoS Attacks

Memcached Servers Abused for Massive Amplification DDoS Attacks
February 27, 2018Swati Khandelwal
Cybercriminals have figured out a way to abuse widely-used Memcached servers to launch over 51,000 times powerful DDoS attacks than their original strength, which could result in knocking down of major websites and Internet infrastructure. In recent days, security researchers at Cloudflare , Arbor Networks , and Chinese security firm Qihoo 360 noticed that hackers are now abusing "Memcached" to amplify their DDoS attacks by an unprecedented factor of 51,200. Memcached is a popular open-source and easily deployable distributed caching system that allows objects to be stored in memory and has been designed to work with a large number of open connections. Memcached server runs over TCP or UDP port 11211. The Memcached application has been designed to speed up dynamic web applications by reducing stress on the database that helps administrators to increase performance and scale web applications. It's widely used by thousands of websites, including Facebook, Flickr,

Unpatched DoS Flaw Could Help Anyone Take Down WordPress Websites

Unpatched DoS Flaw Could Help Anyone Take Down WordPress Websites
February 05, 2018Mohit Kumar
A simple yet serious application-level denial of service (DoS) vulnerability has been discovered in WordPress CMS platform that could allow anyone to take down most WordPress websites even with a single machine—without hitting with a massive amount of bandwidth, as required in network-level DDoS attacks to achieve the same. Since the company has denied patching the issue, the vulnerability ( CVE-2018-6389 ) remains unpatched and affects almost all versions of WordPress released in last nine years, including the latest stable release of WordPress (Version 4.9.2). Discovered by Israeli security researcher Barak Tawily , the vulnerability resides in the way " load-scripts.php ," a built-in script in WordPress CMS, processes user-defined requests. For those unaware, load-scripts.php file has only been designed for admin users to help a website improve performance and load page faster by combining (on the server end) multiple JavaScript files into a single request. Howe

Microsoft Issues Patches For Severe Flaws, Including Office Zero-Day & DNS Attack

Microsoft Issues Patches For Severe Flaws, Including Office Zero-Day & DNS Attack
October 11, 2017Swati Khandelwal
As part of its "October Patch Tuesday," Microsoft has today released a large batch of security updates to patch a total of 62 vulnerabilities in its products, including a severe MS office zero-day flaw that has been exploited in the wild. Security updates also include patches for Microsoft Windows operating systems, Internet Explorer, Microsoft Edge, Skype, Microsoft Lync and Microsoft SharePoint Server. Besides the MS Office vulnerability, the company has also addressed two other publicly disclosed (but not yet targeted in the wild) vulnerabilities that affect the SharePoint Server and the Windows Subsystem for Linux. October patch Tuesday also fixes a critical Windows DNS vulnerability that could be exploited by a malicious DNS server to execute arbitrary code on the targeted system. Below you can find a brief technical explanation of all above mentioned critical and important vulnerabilities. Microsoft Office Memory Corruption Vulnerability (CVE-2017-11826) T

Even A Single Computer Can Take Down Big Servers Using BlackNurse Attack

Even A Single Computer Can Take Down Big Servers Using BlackNurse Attack
November 14, 2016Swati Khandelwal
Yes, you only need a single laptop with a decent internet connection, rather a massive botnet, to launch overwhelming denial of service (DoS) attacks in order to bring down major Internet servers and modern-day firewalls. Researchers at TDC Security Operations Center have discovered a new attack technique that lone attackers with limited resources (in this case, a laptop and at least 15Mbps of bandwidth) can use to knock large servers offline. Dubbed a BlackNurse attack or the low-rate " Ping of Death " attack, the technique can be used to launch several low-volume DoS attacks by sending specially formed Internet Control Message Protocol (ICMP) packets, or 'pings' that overwhelm the processors on server protected by firewalls from Cisco, Palo Alto Networks, among others. ICMP is a protocol used by routers and other networking devices to send and receive error messages. According to a technical report [ PDF ] published this week, the BlackNurse attack is mo

OpenSSL Releases Patch For "High" Severity Vulnerability

OpenSSL Releases Patch For "High" Severity Vulnerability
November 10, 2016Mohit Kumar
As announced on Tuesday, the OpenSSL project team released OpenSSL version 1.1.0c that addresses three security vulnerabilities in its software. The most serious of all is a heap-based buffer overflow bug (CVE-2016-7054) related to Transport Layer Security (TLS) connections using *-CHACHA20-POLY1305 cipher suites. The vulnerability, reported by Robert Święcki of the Google Security Team on September 25, can lead to DoS attack by corrupting larger payloads, resulting in a crash of OpenSSL. The severity of the flaw is rated "High" and does not affect OpenSSL versions prior to 1.1.0. However, the OpenSSL team reports there is no evidence that the flaw is exploitable beyond a DoS attack. The OpenSSL project also patches a moderate severity flaw (CVE-2016-7053) that can cause applications to crash. "Applications parsing invalid CMS structures can crash with a NULL pointer dereference. This is caused by a bug in the handling of the ASN.1 CHOICE type in OpenSSL 1.1.0

Critical DoS Flaw found in OpenSSL — How It Works

Critical DoS Flaw found in OpenSSL — How It Works
September 23, 2016Swati Khandelwal
The OpenSSL Foundation has patched over a dozen vulnerabilities in its cryptographic code library, including a high severity bug that can be exploited for denial-of-service (DoS) attacks. OpenSSL is a widely used open-source cryptographic library that provides encrypted Internet connections using Secure Sockets Layer (SSL) or Transport Layer Security (TLS) for the majority of websites, as well as other secure services. The vulnerabilities exist in OpenSSL versions 1.0.1, 1.0.2 and 1.1.0 and patched in OpenSSL versions 1.1.0a, 1.0.2i and 1.0.1u. The Critical-rated bug ( CVE-2016-6304 ) can be exploited by sending a large OCSP Status Request extension on the targeted server during connection negotiations, which causes memory exhaustion to launch DoS attacks, the OpenSSL Project said . What is OCSP Protocol? OCSP (Online Certificate Status Protocol), supported by all modern web browsers, is a protocol designed to perform verification and obtain the revocation status of a digital

No Password Required! 135 Million Modems Open to Remote Factory Reset

No Password Required! 135 Million Modems Open to Remote Factory Reset
April 09, 2016Swati Khandelwal
More than 135 Million modems around the world are vulnerable to a flaw that can be exploited remotely to knock them offline by cutting off the Internet access. The simple and easily exploitable vulnerability has been uncovered in one of the most popular and widely-used cable modem, the Arris SURFboard SB6141 , used in Millions of US households. Security researcher David Longenecker discovered a loophole that made these modems vulnerable to unauthenticated reboot attacks. He also released his "exploit" after Arris (formerly Motorola) stopped responding to him despite a responsible disclosure. The Bug is quite silly: No Username and Password Protection. Arris does not provide any password authentication set up on the modem's user interface, thus allowing any local attacker to access the administration web interface at 192.168.100.1 without the need to enter a username and password. This issue allows a local attacker to ' Restart Cable Modem '

Aw, Snap! This 16-Character String Can Crash Your Google Chrome

Aw, Snap! This 16-Character String Can Crash Your Google Chrome
September 21, 2015Swati Khandelwal
Remember when it took only 13 characters to crash Chrome browser instantly? This time, it takes 16-character simple URL string of text to crash Google Chrome instantly. Yes, you can crash the latest version of Chrome browser with just a simple tiny URL. To do this, all you need to do is follow one of these tricks: Type a 16-character link and hit enter Click on a 16-character link Just put your cursor on a 16-character link Yes, that's right. You don't even have to open or click the malformed link to cause the crash, putting the cursor on the link is enough to crash your Chrome. All the tricks mentioned above will either kill that particular Chrome tab or kill the whole Chrome browser. The issue was discovered by security researcher Andris Atteka , who explained in his blog post that just by adding a NULL char in the URL string could crash Chrome instantly. Atteka was able to crash the browser with a 26 character long string, which is given b

Android Wi-Fi Direct Vulnerability Lets Hackers to Kick your Devices OFF

Android Wi-Fi Direct Vulnerability Lets Hackers to Kick your Devices OFF
January 27, 2015Swati Khandelwal
Security researchers from Core Security has reportedly found a Denial of Service ( DoS ) attack vulnerability in Android WiFi-Direct. Android's WiFi-Direct is a wireless technology that allows two devices to establish a direct, peer-to-peer Wi-Fi connection without requiring a wireless router. Smartphones have been able to support Wi-Fi Direct for a while now. According to the advisory , the remotely exploitable denial-of-service vulnerability is affecting a wide number of Android mobile devices when it scans for WiFi Direct devices. If exploited, the vulnerability would let an attacker force a reboot of a device. " An attacker could send a specially crafted 802.11 Probe Response frame causing the Dalvik subsystem to reboot because of an Unhandle Exception on WiFiMonitor class ," advisory states. The Android WiFi-Direct vulnerability (CVE-2014-0997) affects: Nexus 5 - Android 4.4.4 Nexus 4 - Android 4.4.4 LG D806 - Android 4.2.2 Samsung SM-T310 - Android

Remote Attack Could Format Your Pebble Smartwatch Easily

Remote Attack Could Format Your Pebble Smartwatch Easily
August 22, 2014Swati Khandelwal
Pebble, a wristwatch that can connect to your phone - both iOS and Android - and interact with apps, has a hard-coded vulnerability that allows a remote attacker to destroy your Smartwatch completely. Pebble Smartwatch , developed and released by Pebble Technology Corporation in 2013, is considered as one of the most popular SmartWatches that had become the most funded project in the history of Kickstarter. Just two hours after its crowd-funding campaign launched, Pebble had already surpassed its $100,000 goal and at last had reached over $10.25 million pledged by nearly 70,000 Kickstarter backers. A security enthusiast Hemanth Joseph  claimed to have found that his Pebble SmartWatch with the latest v2.4.1 Firmware can be remotely exploited by anyone with no technical knowledge in order to delete all data stored in the device, apps, notes, and other information stored in it. HOW PEBBLE SMARTWATCH WORKS Before proceeding towards how he did this, let me explain how Peb

Linux Kernel Vulnerable to Privilege Escalation and DoS Attack

Linux Kernel Vulnerable to Privilege Escalation and DoS Attack
June 07, 2014Swati Khandelwal
Multiple flaws have been identified in Linux Kernel and related software could allow hackers to hack your Linux machines, shared hosting and websites hosted on them. PRIVILEGE ESCALATION VULNERABILITY IN LINUX KERNEL A privilege escalation vulnerability has been identified in the widely used Linux kernel that could allow an attackers to take the control of users' system. On Thursday, the most popular distributor of open source Linux OS, Debian warned about this vulnerability (CVE-2014-3153) in a security update, along with some other vulnerabilities in the Linux kernel that may lead to a denial of service attack. The most critical one is the flaw (CVE-2014-3153) discovered by Pinkie Pie which resides in the futex subsystem call of Linux Kernel 2.6.32.62/3.2.59/3.4.91/3.10.41/3.12.21/3.14.5 versions , leaving a queued kernel waiter on the stack, which can be exploited to potentially execute arbitrary code with kernel mode privileges. " Pinkie Pie discovered an

Google Nexus phone vulnerable to SMS-based DOS attack

Google Nexus phone vulnerable to SMS-based DOS attack
November 30, 2013Mohit Kumar
Google's Nexus Smartphones are vulnerable to SMS-based DOS attack , where an attacker can force it to restart, freeze, or lose network connection by sending a large number of special SMS messages to them. The vulnerability, discovered by Bogdan Alecu , a system administrator at Dutch IT services company Levi9, and affects all Android 4.x firmware versions on Google Galaxy Nexus, Nexus 4 and Nexus 5. The problem is with how the phones handle a special type of text message, known as a flash SMS. By sending around 30 Flash SMS ( Flash SMS is a type of message that normally is not stored by the system and does not trigger any audio alerts ) messages to Nexus phone an attacker can cause the phone to malfunction. He presented the vulnerability on Friday at the DefCamp security conference in Bucharest, Romania. In an email exchange with me, he said ' I was testing different message types and for the class 0 messages I noticed that the popup being displayed also adds an extra layer wh
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