Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Risk

7/5/2007
02:42 AM
Connect Directly
Google+
Twitter
RSS
E-Mail
50%
50%

Meet the Next-Gen Web Worm

New mutating Web worm evades scanners and even uses bug reports to propagate

Up to now, Web-borne worms couldn't be easily spread from host to host, and they have usually been easy to detect. But two researchers have written a proof-of-concept of a more deadly and persistent Web worm that can run in both the client's browser and on a Web server -- and evades signature-based scans.

The so-called "hybrid Web worm" has more staying power than previous Web worms -- such as the infamous Samy worm that infected MySpace -- that were restricted to specific hosts and domains, and typically only exploited a single vulnerability.

"As [researcher] HD Moore put it, [these older Web worms] were like a smallpox epidemic on a small island," says Billy Hoffman, lead researcher for SPI Dynamics' Labs and co-author of the hybrid worm proof-of-concept. "Samy couldn't leave MySpace."

At the Black Hat conference next month, Hoffman and fellow researcher John Terrill will demonstrate their wily, next-generation Web worm in a session entitled "The Little Hybrid Web Worm that Could." Their new worm mutates to evade signature detection -- it can even use vulnerability information from sites like Secunia to infect other servers and browsers.

"We're going to demonstrate how it can pull new vulnerability information in the wild and start using it" to spread, Hoffman says.

Hoffman and Terrill, who is executive vice president of Enterprise Management Technology, have only built out the client side of the attack, and they won't release the POC, because they don't want the potentially lethal code to fall into the wrong hands.

"We didn't want to build something truly evil," Hoffman says. "This is a proof-of-concept on the client, but it would work on the server, too."

Although current Web worm attacks are easily detectable and restricted to a single host, they are still more sophisticated than predecessor email-based attacks, because they can use JavaScript and Flash to run across disparate operating systems.

But the hybrid Web worm is even more intelligent. When it's injected into a Web server, it can write a JavaScript version of itself into Web pages, so that when a user visits those sites, it infects his or her browser. "We came up with a way for it to update its vulnerabilities while in the wild, " Hoffman says.

It grabs, and then exploits, new vulnerabilities reported on sites such as Secunia and then continues propagating. "Secunia's [vulnerability data] is machine-consumable, so it could pick up new vulnerabilities while it's in the wild" and spread via those bugs as well, Hoffman says.

This polymorphic feature of the next-generation worm is a natural evolution for the malware -- and it will be tough for enterprises to defend against, Hoffman says. "Trying to use signatures on these worms isn't going to work."

One hope for detection is to study the malware's behavior for worm-like characteristics, Hoffman says. Even though the hybrid worm is mutating, it still behaves like any other worm: "We are trying to think about what a worm does, versus its source code."

He says he and Terrill also will discuss at Black Hat ways to attempt to "signature" a mutating Web worm, as well as detecting infected machines based on the traffic they generate when they look for and infect other machines.

— Kelly Jackson Higgins, Senior Editor, Dark Reading

  • SPI Dynamics Kelly Jackson Higgins is the Executive Editor of Dark Reading. She is an award-winning veteran technology and business journalist with more than two decades of experience in reporting and editing for various publications, including Network Computing, Secure Enterprise ... View Full Bio

    Comment  | 
    Print  | 
    More Insights
  • Comments
    Newest First  |  Oldest First  |  Threaded View
    Register for Dark Reading Newsletters
    White Papers
    Video
    Cartoon Contest
    Current Issue
    6 Emerging Cyber Threats That Enterprises Face in 2020
    This Tech Digest gives an in-depth look at six emerging cyber threats that enterprises could face in 2020. Download your copy today!
    Flash Poll
    State of Cybersecurity Incident Response
    State of Cybersecurity Incident Response
    Data breaches and regulations have forced organizations to pay closer attention to the security incident response function. However, security leaders may be overestimating their ability to detect and respond to security incidents. Read this report to find out more.
    Twitter Feed
    Dark Reading - Bug Report
    Bug Report
    Enterprise Vulnerabilities
    From DHS/US-CERT's National Vulnerability Database
    CVE-2020-10696
    PUBLISHED: 2020-03-31
    A path traversal flaw was found in Buildah in versions before 1.14.5. This flaw allows an attacker to trick a user into building a malicious container image hosted on an HTTP(s) server and then write files to the user's system anywhere that the user has permissions.
    CVE-2020-5344
    PUBLISHED: 2020-03-31
    Dell EMC iDRAC7, iDRAC8 and iDRAC9 versions prior to 2.65.65.65, 2.70.70.70, 4.00.00.00 contain a stack-based buffer overflow vulnerability. An unauthenticated remote attacker may exploit this vulnerability to crash the affected process or execute arbitrary code on the system by sending specially cr...
    CVE-2020-5292
    PUBLISHED: 2020-03-31
    Leantime before versions 2.0.15 and 2.1-beta3 has a SQL Injection vulnerability. The impact is high. Malicious users/attackers can execute arbitrary SQL queries negatively affecting the confidentiality, integrity, and availability of the site. Attackers can exfiltrate data like the users' and admini...
    CVE-2020-7009
    PUBLISHED: 2020-03-31
    Elasticsearch versions from 6.7.0 to 6.8.7 and 7.0.0 to 7.6.1 contain a privilege escalation flaw if an attacker is able to create API keys. An attacker who is able to generate an API key can perform a series of steps that result in an API key being generated with elevated privileges.
    CVE-2019-13495
    PUBLISHED: 2020-03-31
    In firmware version 4.50 of Zyxel XGS2210-52HP, multiple stored cross-site scripting (XSS) issues allows remote authenticated users to inject arbitrary web script via an rpSys.html Name or Location field.