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A critical vulnerability has been discovered in Systemd , the popular init system and service manager for Linux operating systems, that could allow remote attackers to potentially trigger a buffer overflow to execute malicious code on the targeted machines via a DNS response. The vulnerability, designated as CVE-2017-9445 , actually resides in the ' dns_packet_new ' function of 'systemd-resolved,' a DNS response handler component that provides network name resolution to local applications. According to an advisory published Tuesday, a specially crafted malicious DNS response can crash 'systemd-resolved' program remotely when the system tries to lookup for a hostname on an attacker-controlled DNS service. Eventually, large DNS response overflows the buffer, allowing an attacker to overwrite the memory which leads to remote code execution. This means the attackers can remotely run any malware on the targeted system or server via their evil DNS service

Remember SambaCry ? Two weeks ago we reported about a 7-year-old critical remote code execution vulnerability in Samba networking software (re-implementation of SMB networking protocol) that allows a remote hacker to take full control of a vulnerable Linux and Unix machines. To know more about the SambaCry vulnerability (CVE-2017-7494) and how it works, you can read our previous article . At that time, nearly 485,000 Samba-enabled computers were found to be exposed on the Internet, and researchers predicted that the SambaCry-based attacks also have potential to spread just like WannaCry ransomware widely. The prediction came out to be quite accurate, as honeypots set up by the team of researchers from Kaspersky Lab have captured a malware campaign that is exploiting SambaCry vulnerability to infect Linux computers with cryptocurrency mining software. Another security researcher, Omri Ben Bassat‏, independently discovered  the same campaign and named it "EternalMiner

Over the past two years, a shocking  51% of organizations surveyed in a leading industry report have been compromised by a cyberattack.  Yes, over half.  And this, in a world where enterprises deploy  an average of 53 different security solutions  to safeguard their digital domain.  Alarming? Absolutely. A recent survey of CISOs and CIOs, commissioned by Pentera and conducted by Global Surveyz Research, offers a quantifiable glimpse into this evolving battlefield, revealing a stark contrast between the growing risks and the tightening budget constraints under which cybersecurity professionals operate. With this report, Pentera has once again taken a magnifying glass to the state of pentesting to release its annual report about today's pentesting practices. Engaging with 450 security executives from North America, LATAM, APAC, and EMEA—all in VP or C-level positions at organizations with over 1,000 employees—the report paints a current picture of modern security validation prac

Another dangerous vulnerability has been discovered in Linux kernel that dates back to 2009 and affects a large number of Linux distros, including Red Hat, Debian, Fedora, OpenSUSE, and Ubuntu. The latest Linux kernel flaw ( CVE-2017-2636 ), which existed in the Linux kernel for the past seven years, allows a local unprivileged user to gain root privileges on affected systems or cause a denial of service (system crash). Positive Technologies researcher Alexander Popov discovered a race condition issue in the N_HLDC Linux kernel driver – which is responsible for dealing with High-Level Data Link Control (HDLC) data – that leads to double-free vulnerability. " Double Free " is one of the most common memory corruption bug that occurs when the application releases same memory location twice by calling the free() function on the same allocated memory. An unauthenticated attacker may leverage this vulnerability to inject and execute arbitrary code in the security context of curren

No software is immune to being Hacked! Not even Linux. A security researcher has discovered a critical vulnerability in Ubuntu Linux operating system that would allow an attacker to remotely compromise a target computer using a malicious file. The vulnerability affects all default Ubuntu Linux installations versions 12.10 (Quantal) and later. Researcher Donncha O'Cearbhaill discovered the security bug which actually resides in the Apport crash reporting tool on Ubuntu. A successful exploit of this CrashDB code injection issue could allow an attacker to remotely execute arbitrary code on victim's machine. All an attacker needs is to trick the Ubuntu user into opening a maliciously booby-trapped crash file. This would inject malicious code in Ubuntu OS's crash file handler, which when parsed, executes arbitrary Python code. "The code first checks if the CrashDB field starts with { indicating the start of a Python dictionary," O'Cearbhaill explain

A 5-year-old serious privilege-escalation vulnerability has been discovered in Linux kernel that affects almost every distro of the Linux operating system, including Redhat, and Ubuntu. Over a month back, a nine-year-old privilege-escalation vulnerability, dubbed " Dirty COW ," was discovered in the Linux kernel that affected every distro of the open-source operating system, including Red Hat, Debian, and Ubuntu. Now, another Linux kernel vulnerability ( CVE-2016-8655 ) that dates back to 2011 disclosed today could allow an unprivileged local user to gain root privileges by exploiting a race condition in the af_packet implementation in the Linux kernel. Philip Pettersson, the researcher who discovered the flaw, was able to create an exploit to gain a root shell on an Ubuntu 16.04 LTS system (Linux Kernel 4.4) and also defeated SMEP/SMAP (Supervisor Mode Execution Prevention/Supervisor Mode Access Prevention) protection to gain kernel code execution abilities. In

A hacker with little more than a minute can bypass the authentication procedures on some Linux systems just by holding down the Enter key for around 70 seconds. The result? The act grants the hacker a shell with root privileges, which allows them to gain complete remote control over encrypted Linux machine. The security issue relies due to a vulnerability ( CVE-2016-4484 ) in the implementation of the Cryptsetup utility used for encrypting hard drives via Linux Unified Key Setup (LUKS), which is the standard implementation of disk encryption on a Linux-based operating system. The flaw actually is in the way the Cryptsetup utility handles password failures for the decryption process when a system boots up, which lets a user retry the password multiple times. What's even worse? Even if the user has tried up all 93 password attempts, the user is dropped to a shell (Busybox in Ubuntu) that has root privileges. In other words, if you enter a blank password 93 times – or s

Unlike specially crafted malware specifically developed to take advantage of Windows operating system platform, cyber attackers have started creating cross-platform malware for wider exploitation. Due to the rise in popularity of Mac OS X and other Windows desktop alternatives, hackers have begun designing cross-platform malware modularly for wide distribution. Cross-platform malware is loaded with specialized payloads and components, allowing it to run on multiple platforms. One such malware family has recently been discovered by researchers at Kaspersky Lab, which run on all the key operating systems, including Windows, Linux, and Mac OS X. Stefan Ortloff, a researcher from Kaspersky Lab's Global Research and Analysis Team, first discovered the Linux and Windows variants of this family of cross-platform backdoor, dubbed Mokes , in January this year. Now, the researcher today confirmed the existence of an OS X variant of this malware family, explaining a technical breakd

An estimated 80 percent of Android smartphones and tablets running Android 4.4 KitKat and higher are vulnerable to a recently disclosed Linux kernel flaw that allows hackers to terminate connections, spy on unencrypted traffic or inject malware into the parties' communications. Even the latest Android Nougat Preview is considered to be vulnerable. The security flaw was first appeared in the implementation of the TCP protocol in all Linux systems deployed since 2012 (version 3.6 and above of the Linux OS kernel) and the Linux Foundation has already patched the Linux kernel on July 11, 2016. However, the vulnerability ( CVE-2016-5696 ) is now affecting a large portion of the Android ecosystem. According to a blog post published Monday by mobile security firm Lookout, the Linux flaw is present in Android version 4.4 KitKat and all future releases, including the latest developer preview of Android Nougat . Around 1.4 BILLLLLION Android Devices Affected This means that 80%

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

A new critical zero-day vulnerability has been discovered in the Linux kernel that could allow attackers to gain root level privileges by running a malicious Android or Linux application on an affected device. The critical Linux kernel flaw ( CVE-2016-0728 ) has been identified by a group of researchers at a startup named Perception Point. The vulnerability was present in the code since 2012, and affects any operating system with Linux kernel 3.8 and higher , so there are probably tens of millions of computers, both 32-bit and 64-bit, exposed to this flaw. However, the most bothersome part is that the problem affects Android versions KitKat and higher , which means about 66 percent of all Android devices are also exposed to the serious Linux kernel flaw. Impact of the Zero-Day Vulnerability An attacker would only require local access to exploit the flaw on a Linux server. If successfully exploited, the vulnerability can allow attackers to get root access

Thousands of computers and web servers running Linux and FreeBSD operating systems have been infected over past five years with sophisticated malware that turn the machines into spambots. The new Linux malware, discovered by the security researchers from the antivirus provider Eset, has been dubbed " Mumblehard " because it is Muttering spam from your servers , says Eset 23-page long report (PDF) titled "Unboxing Linux/Mumblehard." Researchers have logged more than 8,500 unique IP addresses during the seven months period of research that were hit by Mumblehard Linux malware and found over 3,000 machines joined them in the past three weeks. Mumblehard features two basic components: Backdoor  Spamming daemon  Both written in the Perl programming language and "feature the same custom packer written in assembly language." The backdoor allows hackers to infiltrate into the system and control the command and control servers, and t

Security researchers have find out ways to hijack the Intel-compatible PCs running Linux by exploiting the physical weaknesses in certain varieties of DDR DRAM (double data rate dynamic random-access memory) chips and gaining higher kernel privileges on the system. The technique, dubbed " rowhammer ", was outlined in a blog post published Monday by Google's Project Zero security initiative, a team of top security researchers dedicatedly identifies severe zero-day vulnerabilities in different software. Rowhammer is a problem with recent generation DRAM chips in which repeatedly accessing a row of memory can cause " bit flipping " in an adjacent row which could allow anyone to change the value of contents stored in computer memory. WHAT IS ROWHAMMER BUG DDR memory is arranged in an array of rows and columns, which are assigned to various services, applications and OS resources in large blocks. In order to prevent each application from access

The GHOST vulnerability is a buffer overflow condition that can be easily exploited locally and remotely, which makes it extremely dangerous. This vulnerability is named after the GetHOSTbyname function involved in the exploit. Attackers utilize buffer overflow vulnerabilities like this one by sending specific packets of data to a vulnerable system. The attack allows the attacker to execute arbitrary code and take control of the victim's vulnerable machine. Unfortunately, the vulnerability exists in the GNU C Library (glibc) , a code library originally released in 2000, meaning it has been widely distributed. Many derivative programs utilize the glibc to carry out common tasks. Although an update released by Linux in 2013 mitigated this vulnerability, most systems and products have not installed the patch. What Can I Do About GHOST Vulnerability? Like with any vulnerability, the best way to mitigate GHOST vulnerability is to identify vulnerable systems, prioritize th

The open-source Wget application which is most widely used on Linux and Unix systems for retrieving files from the web has found vulnerable to a critical flaw. GNU Wget is a command-line utility designed to retrieve files from the Web using HTTP, HTTPS, and FTP, the most widely used Internet protocols. Wget can be easily installed on any Unix-like system and has been ported to many environments, including Microsoft Windows, Mac OS X, OpenVMS, MorphOS and AmigaOS. When a recursive directory fetch over FTP server as the target, it would let an attacker " create arbitrary files, directories or symbolic links " due to a symlink flaw. IMPACT OF SYMLINK ATTACK " It was found that wget was susceptible to a symlink attack which could create arbitrary files, directories or symbolic links and set their permissions when retrieving a directory recursively through FTP ," developer Vasyl Kaigorodov wrote in a Red Hat Bugzilla comment . A remote unauthentica

On one hand where more than half of the Internet is considering the Bash vulnerability to be severe, Apple says the vast majority of Mac computer users are not at risk from the recently discovered vulnerability in the Bash command-line interpreter – aka the " Shellshock " bug that could allow hackers to take over an operating system completely. Apple has issued a public statement in response to this issue, assuring its OS X users that most of them are safe from any potential attacks through the ShellShock Vulnerability , which security experts have warned affect operating systems, including Mac's OS X. " The vast majority of OS X users are not at risk to recently reported bash vulnerabilities ," Apple said. " Bash, a UNIX command shell and language included in OS X, has a weakness that could allow unauthorized users to remotely gain control of vulnerable systems. With OS X, systems are safe by default and not exposed to remote exploits of bash unl

Security researchers from Russian Internet giant Yandex have discovered a new piece of malware that is being used to target Linux and FreeBSD web servers in order to make them a part of the wide botnet, even without the need of any root privileges. Researchers dubbed the malware as Mayhem, a nasty malware modular that includes a number of payloads to cause malicious things and targets to infect only those machines which are not updated with security patches or less likely to run security software. So far, researchers have found over 1,400 Linux and FreeBSD servers around the world that have compromised by the malware , with potentially thousands more to come. Most of the compromised machines are located in the USA, Russia, Germany and Canada. Three security experts, Andrej Kovalev, Konstantin Ostrashkevich and Evgeny Sidorov , who work at Russia-based Internet portal Yandex, discovered the malware targeting *nix servers . They were able to trace transmissions from th

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