Server Security

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BIND glitches could trigger DoS attacks

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Security organizations have issued an alert about a BIND vulnerability which could see companies face denial-of-service attacks. The vulnerability is found in version 9 of the Internet Software Consortium's BIND (Berkeley Internet Name Domain) server. If it's exploited by an . . .

Writing PAM Modules, Part Three

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PAM stands for Pluggable Authentication Modules and is a system for providing application independence for authentication. A PAM-enabled application calls a stack of PAM modules to run authentication, open and close sessions, and check account validity.. . .

New security attack identified: Denial of Responsibility (DoR)

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A recent report from the National Association for Security and Trust Evaluation warns of an increase in serious security breaches known as Denial of Responsibility (DoR) attacks. "Each attack is much more dangerous than traditional security flaws," says Warren N. Veighn of the Association, "because the extent of the vulnerabilities is so great, the time they affect deployed systems can stretch out to decades, and getting the source of the problem to react appropriately is by definition very difficult." . . .

Linux.Simile: Windows Virus that affects Linux Too?

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{Win32,Linux}/Simile.D is a very complex virus that uses entry-point obscuring, metamorphism, and polymorphic decryption. It is the first known polymorphic metamorphic virus to infect under both Windows and Linux. The virus contains no destructive payload, but infected files may display messages . . .

SQL Injection Walkthrough

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When a machine has only port 80 opened, your most trusted vulnerability scanner cannot return anything useful, and you know that the admin always patch his server, we have to turn to web hacking. SQL injection is one of type of . . .

File Locking Local Denial of Service: Impact on Sendmail

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This article discuss how sendmail currently handles file locking and how it will change in future versions. "Any application which uses either flock() or fcntl() style locking or other APIs that use one of these locking methods (such as open() with O_EXLOCK and O_SHLOCK) on files readable by other local untrusted users may be susceptible to local denial of service attacks.". . .

Comment: Web sites insecure as ever

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Most, if not all, of corporate web sites are fundamentally insecure. And this insecurity can allow attackers to access databases, delete or change information, and cause absolute chaos with very little effort or technical know how. . . .

How Can You Defend Against a Superworm?

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Give an exploit to script kiddies, and they'll hit every vulnerable host in weeks. Build a worm with it, and it could take days. How long would a superworm take? Try 30 seconds. Brandon Wiley explains superworms and some possible self-defense . . .

Tips on basic Linux server security

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If you just put your Apache web server online, and are thinking into making the first step in your system security, this brief article will help you do that. By having your own server, you must understand the responsibility behind it. . . .

XP Updates Start to P.O. Users

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As many as three times a week, on average, XP users see a little window pop-up at the bottom of their computer screens announcing the availability of another new update for their system. This plethora of patches has left many users wondering whether their hard drives are big enough to handle "Trustworthy Computing.". . .

Cookies Take A Bite Out Of Security

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As if IT managers didn't have enough security headaches, the rise of Web site-based intrusions has risen over the last year, with aggressive cookies and pop-up-spawned spyware leading the charge. Products like the Gator password manager utility are reported to include a Web-user monitoring component, which may even cause Web browsers to crash or behave erratically.. . .

Potential Vulnerability in LIDS 1.1.1

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There is a possibility to use a capability from LIDS protected binaries for arbitrary users. For example if some binary has the CAP_SETUID capability granted, a general user can execute this binary under a arbitrary user ( could be the root ).. . .

Denial-of-service attacks still a threat

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Denial-of-service (DOS) attacks continue to present a significant security threat to corporations two years after a spate of incidents brought down several high-profile sites, including those of Yahoo Inc. and eBay Inc., users and analysts report. Since then, several technologies . . .

Server port 80 plagues Internet security

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THE INTERNET HAS become a riskier place for businesses since the fall of 2001 and doesn't look to be any more secure in the near future, according to security firm Internet Security Systems, which released its security incident figures for the first quarter of 2002 Wednesday. . . .

How to set up IMAP on the cheap, Part 2

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This is the second in a series of articles about how to install and configure the Cyrus IMAP mail server, Postfix SMTP, and Procmail for server-side mail filtering. Last week, we covered the installation and basic configuration for Cyrus IMAP.. . .