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The Hacker News - Cybersecurity News and Analysis: Linux server

Sudo Flaw Lets Linux Users Run Commands As Root Even When They're Restricted

Sudo Flaw Lets Linux Users Run Commands As Root Even When They're Restricted
October 14, 2019Mohit Kumar
Attention Linux Users! A new vulnerability has been discovered in Sudo —one of the most important, powerful, and commonly used utilities that comes as a core command installed on almost every UNIX and Linux-based operating system. The vulnerability in question is a sudo security policy bypass issue that could allow a malicious user or a program to execute arbitrary commands as root on a targeted Linux system even when the "sudoers configuration" explicitly disallows the root access. Sudo, stands for "superuser do," is a system command that allows a user to run applications or commands with the privileges of a different user without switching environments—most often, for running commands as the root user. By default on most Linux distributions, the ALL keyword in RunAs specification in /etc/sudoers file, as shown in the screenshot, allows all users in the admin or sudo groups to run any command as any valid user on the system. However, since privilege separ

Hackers Planted Backdoor in Webmin, Popular Utility for Linux/Unix Servers

Hackers Planted Backdoor in Webmin, Popular Utility for Linux/Unix Servers
August 20, 2019Mohit Kumar
Following the public disclosure of a critical zero-day vulnerability in Webmin last week, the project's maintainers today revealed that the flaw was not actually the result of a coding mistake made by the programmers. Instead, it was secretly planted by an unknown hacker who successfully managed to inject a backdoor at some point in its build infrastructure—that surprisingly persisted into various releases of Webmin (1.882 through 1.921) and eventually remained hidden for over a year. With over 3 million downloads per year, Webmin is one of the world's most popular open-source web-based applications for managing Unix-based systems, such as Linux, FreeBSD, or OpenBSD servers. Webmin offers a simple user interface (UI) to manage users and groups, databases, BIND, Apache, Postfix, Sendmail, QMail, backups, firewalls, monitoring and alerts, and much more. The story started when Turkish researcher Özkan Mustafa Akkuş publicly presented a zero-day remote code execution vul

IBM Buys "Red Hat" Open-Source Software Company for $34 Billion

IBM Buys "Red Hat" Open-Source Software Company for $34 Billion
October 29, 2018Swati Khandelwal
It's been quite a year for the open source platforms. Earlier this year, Microsoft acquired popular code repository hosting service GitHub for $7.5 billion , and now IBM has just announced the biggest open-source business deal ever. IBM today confirmed that it would be acquiring open source Linux firm Red Hat for $190 per share in cash, working out to a total value of approximately $34 billion. Red Hat, known for its Red Hat Enterprise Linux (RHEL) operating system, is a leading software company that offers open-source software products to the enterprise community. Even Oracle uses Red Hat's source code for its Oracle Linux product. Red Hat's last year revenue was $2.4 billion, and this year the company has earned $2.9 billion. But if Red Hat products are open source and updates are free, you might be wondering how does the company earn. Red Hat was one of the first companies who found a successful way to make money from free open-source software. It offers consul

New Privilege Escalation Flaw Affects Most Linux Distributions

New Privilege Escalation Flaw Affects Most Linux Distributions
October 26, 2018Mohit Kumar
An Indian security researcher has discovered a highly critical flaw in X.Org Server package that impacts OpenBSD and most Linux distributions, including Debian, Ubuntu, CentOS, Red Hat, and Fedora. Xorg X server is a popular open-source implementation of the X11 system (display server) that offers a graphical environment to a wider range of hardware and OS platforms. It serves as an intermediary between client and user applications to manage graphical displays. According to a blog post published by software security engineer Narendra Shinde , Xorg X server doesn't correctly handle and validate arguments for at least two command-line parameters, allowing a low-privileged user to execute malicious code and overwrite any file—including files owned by privileged users like root. The flaw, tracked as CVE-2018-14665 , was introduced in X.Org server 1.19.0 package that remained undetected for almost two years and could have been exploited by a local attacker on the terminal or vi

Your Linux Machine Can Be Hacked Remotely With Just A Malicious DNS Response

Your Linux Machine Can Be Hacked Remotely With Just A Malicious DNS Response
June 29, 2017Swati Khandelwal
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

Web Hosting Company Pays $1 Million to Ransomware Hackers to Get Files Back

Web Hosting Company Pays $1 Million to Ransomware Hackers to Get Files Back
June 19, 2017Mohit Kumar
South Korean web hosting provider has agreed to pay $1 million in bitcoins to hackers after a Linux ransomware infected its 153 servers, encrypting 3,400 business websites and their data, hosted on them. According to a blog post published by NAYANA, the web hosting company, this unfortunate event happened on 10th June when ransomware malware hit its hosting servers and attacker demanded 550 bitcoins (over $1.6 million) to unlock the encrypted files. However, the company later negotiated with the cyber criminals and agreed to pay 397.6 bitcoins (around $1.01 million) in three installments to get their files decrypted. The hosting company has already paid two installments at the time of writing and would pay the last installment of ransom after recovering data from two-third of its infected servers. According to the security firm Trend Micro , the ransomware used in the attack was Erebus that was first spotted in September last year and was seen in February this year with Win

Linux TCP Flaw allows Hackers to Hijack Internet Traffic and Inject Malware Remotely

Linux TCP Flaw allows Hackers to Hijack Internet Traffic and Inject Malware Remotely
August 11, 2016Swati Khandelwal
If you are using the Internet, there are the possibilities that you are open to attack. The Transmission Control Protocol (TCP) implementation in all Linux systems deployed since 2012 ( version 3.6 and above of the Linux kernel ) poses a serious threat to Internet users, whether or not they use Linux directly. This issue is troubling because Linux is used widely across the Internet, from web servers to Android smartphones, tablets, and smart TVs. Researchers have uncovered a serious Internet flaw, which if exploited, could allow attackers to terminate or inject malware into unencrypted communication between any two vulnerable machines on the Internet. The vulnerability could also be used to forcefully terminate HTTPS encrypted connections and downgrade the privacy of secure connections, as well as also threatens anonymity of Tor users by routing them to certain malicious relays. The flaw actually resides in the design and implementation of the Request for Comments: 5961 ( RF

Someone Just Leaked Hard-Coded Password Backdoor for Fortinet Firewalls

Someone Just Leaked Hard-Coded Password Backdoor for Fortinet Firewalls
January 13, 2016Swati Khandelwal
Are millions of enterprise users, who rely on the next-generation firewalls for protection, actually protected from hackers? Probably Not. Just less than a month after an unauthorized backdoor found in Juniper Networks firewalls, an anonymous security researcher has discovered highly suspicious code in FortiOS firewalls from enterprise security vendor Fortinet. According to the leaked information, FortiOS operating system, deployed on Fortinet's FortiGate firewall networking equipment, includes an SSH backdoor that can be used to access its firewall equipment. Anyone can Access FortiOS SSH Backdoor Anyone with " Fortimanager_Access " username and a hashed version of the " FGTAbc11*xy+Qqz27 " password string, which is hard coded into the firewall, can login into Fortinet's FortiGate firewall networking equipment. However, according to the company's product details, this SSH user is created for challenge-and-response authenti

Linux Ransomware targeting Servers and Threatening Webmasters to Pay

Linux Ransomware targeting Servers and Threatening Webmasters to Pay
November 09, 2015Swati Khandelwal
Since past few years, Ransomware has emerged as one of the catastrophic malware programs that lets hacker encrypts all the contents of a victim's hard drive or/and server and demands ransom (typically to be paid in Bitcoin ) in exchange for a key to decrypt it. Until now cyber criminals were targeting computers, smartphones and tablets, but now it appears they are creating ransomware that makes the same impact but for Web Sites – specifically holding files, pages and images of the target website for Ransom. Dubbed Linux.Encoder.1 by Russian antivirus firm Dr.Web , the new strain of ransomware targets Linux-powered websites and servers by encrypting MySQL, Apache, and home/root folders associated with the target site and asking for 1 Bitcoin ( ~ $300 ) to decrypt the files. The ransomware threat is delivered to the target website through known vulnerabilities in website plugins or third-party software. Must Read: FBI Suggests Ransomware Victims — 'Just Pay th

New Release: Kali Linux for Docker — Deploy and Play!

New Release: Kali Linux for Docker — Deploy and Play!
May 27, 2015Mohit Kumar
The Developers of one of the most advanced open source operating system for penetration testing called ' KALI Linux ' have made the operating system available for Docker-addicted system administrators. But, What's Docker? Docker is a new open-source container technology, released in June 2014, that automates the deployment of applications inside self-sufficient software containers by providing an additional layer of abstraction and automation of operating-system-level visualization on Linux. Docker, built on top of Linux containers, is simply a way of managing multiple containers on a single machine. Nowadays, companies are adopting Docker at a remarkable rate. Docker is not just the favorite of Linux powers like RedHat and Canonical, but also big software firms, including Microsoft, which has embraced Docker. Why bringing Kali Linux for Docker? The same was happened to the developer of Offensive Security, who was requested for a Dockerised image of

Hackers Using 'Shellshock' Bash Vulnerability to Launch Botnet Attacks

Hackers Using 'Shellshock' Bash Vulnerability to Launch Botnet Attacks
September 27, 2014Mohit Kumar
Researchers on Thursday discovered a critical remotely exploitable vulnerability in the widely used command-line shell GNU Bourne Again Shell ( Bash ), dubbed " Shellshock " which affects most of the Linux distributions and servers worldwide, and may already have been exploited in the wild to take over Web servers as part of a botnet that is currently trying to infect other servers as well. BOTNET ATTACK IN THE WILD The bot was discovered by the security researcher with the Twitter handle @yinettesys , who reported it on Github and said it appeared to be remotely controlled by miscreants, which indicates that the vulnerability is already being used maliciously by the hackers. The vulnerability (CVE-2014-6271) , which came to light on Wednesday, affects versions 1.14 through 4.3 of GNU Bash and could become a dangerous threat to Linux/Unix and Apple users if the patches to BASH are not applied to the operating systems. However, the patches for the vulnerabil

Mayhem — A New Malware Targets Linux and FreeBSD Web Servers

Mayhem — A New Malware Targets Linux and FreeBSD Web Servers
July 25, 2014Swati Khandelwal
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
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