ZDNet UK / News and Analysis / Business of IT / IT Strategy

Klez virus passes confidential info

By Staff, CNet, 22 April, 2002 10:16

Daily Newsletters

Sign up to ZDNet UK's daily newsletter.

Topics

Email, Attachment, variant, file, klez, klez.h, release information, Viruses

NEWS
The latest variant of the Klez worm sometimes chooses to hitch a ride on sensitive documents, resulting in victims' confidential information spreading with the malicious program, Russian antivirus firm Kaspersky Labs said on Friday. Known as Klez.G, Klez.H and Klez.K, depending on the security advisory, the newest incarnation has spread worldwide, sending itself in email messages with infected documents attached. Occasionally the documents contain sensitive material, said an advisory from Kaspersky Labs. "Klez.H poses a special threat: the worm scans the disks of an infected computer and, depending on a set of conditions, attaches a file to each infected email it distributes," stated the advisory. Text, HTML (Hypertext Markup Language), Adobe Acrobat and Excel files are included in the types of documents that the virus can forward, but other files that the worm could attach -- such as JPEG and MPEG files -- are less likely to contain important information. Representatives of Kaspersky Labs were not available for comment. This is not the first time a virus has leaked information, however. The SirCam worm, which is still spreading among computers on the Internet, also attached itself to documents and forwarded on the infected files to potential victims. Security-software maker Symantec upgraded on Wednesday the latest variant, which it labelled W32.Klez.H, to a threat level of three from a previous rating of two. The company categorises threats on a scale of one, the lowest threat, to five. However, Vincent Weafer, senior director of Symantec's Security Response team, on Friday said they haven't been able to reproduce the information-leaking function of the worm that Kaspersky Labs is claiming. "It is nothing that we have seen in our lab," he said. "It definitely data mines files for email addresses, but we haven't seen it attach files. We will keep doing some additional testing in this area." Email security firm MessageLabs said the Klez.H worm had proliferated "dramatically" during the day on Friday. MessageLabs, based in the United Kingdom, first detected the new variant on Monday from an Internet address in China. Most antivirus vendors, such as Symantec, McAfee and Sophos, have offered Klez.H patches since Wednesday. MessageLabs said it stopped two copies of Klez variants on Monday. Since Wednesday afternoon the number of copies rose sharply, gathering pace on Friday. The firm said it stopped several thousand copies on Friday, for a total of more than 46,000 copies by Friday afternoon -- or nearly one in every 77 emails. The United Kingdom topped its list with more than 5,000 copies stopped, followed by Hong Kong and the United States. The worm arrives in an email message with one of 120 possible subject lines. In many circumstances, the worm doesn't need the victim to open it in order to run. Instead, it takes advantage of a 12-month-old vulnerability in Microsoft Outlook, known as the Automatic Execution of Embedded MIME Type bug, to open itself automatically on un-patched versions of Outlook. The program will also cull email addresses by searching a host of different file types on the infected PC. Using its own mail program, the worm will send itself off to those email addresses. In addition, it will use the addresses to create a fake "From:" field in the email message, disguising the actual source of the email. The worm also attempts to disable antivirus software by deleting registry keys, stopping running processes and removing virus-definition files. Finally, the worm drops a second virus on the computer and spreads to other disk drives connected to the PC over an internal network. Matthew Broersma contributed to this report.
For all security-related news, including updates on the latest viruses, hacking exploits and patches, check out ZDNet UK's Viruses and Hacking News Section. Have your say instantly, and see what others have said. Go to the Security forum. Let the editors know what you think in the Mailroom.

Related stories

Klez worm variant infests UK

Klez worm on the loose again

Heart of England NHS begins massive digitisation plan

Post your comment

In order to post a comment you need to be registered and logged in.

You can also log in with Facebook. Log in or create your ZDNet UK account below

  • Login

Will not be displayed with your comment

By signing up for this service, you indicate that you agree to our Terms and Conditions and have read and understood our Privacy Policy. Questions about membership? Find the answers in the Community FAQ

Get ZDNet UK's daily newsletter

Enter your email address to sign up

ZDNet UK Live

BrownieBoy

@Jack, > Works really well for thieves.... Nice attempt to deflect the argument by tossing in a point that's totally irrelevant, even it were...

6 hours ago by BrownieBoy on AMD Ultrathins to challenge Intel Ultrabooks
bootlegger

Make that 13 people now - I got refused today at Manchester airport. I thought I was up to date on this legislation - I knew of the EU ruling from...

9 hours ago by bootlegger on UK airport body scans will not be opt out
tinycg

Don't forget to check out apps like GoodReader or SlideShark either, they're indispensible for people on the go in presentation situations. Best...

12 hours ago by tinycg on Four top iPad apps for people on the move
TerryRK

Well it seems there is something a number of us agree on. Why is the Ubuntu Unity launcher so ugly? I thought perhaps it was something to do with...

16 hours ago by TerryRK on A tale of two distros: Ubuntu and Linux Mint
Freebies202

Duplicate comments are not made intentionally. Its very good to know that now you are keeping check on this problem because sometimes a commenter...

1 day ago by Freebies202 on Microsoft fixes blog comments, speeds up blogs with open source
kevinmchapman

"the very significant number of users" and "many (most) of us" - you have no evidence for these statements. It is a fact that most users are saying...

1 day ago by kevinmchapman on A tale of two distros: Ubuntu and Linux Mint
Marg Menzies Harrison

Another grammar faux pas is the improper use of "you". When sitting down down in a restaurant, for example, I get cringe when the waitress...

1 day ago by Marg Menzies Harrison via Facebook on 10 flagrant grammar mistakes that make you look stupid
zdnetukuser

And NOW, folks, for Canonical's next trick... Kubuntu is late. Here's a pencil. Draw your own conclusions. cf.:...

1 day ago by zdnetukuser on Linux Minterface
Moley

@kevinmchapman. The discussion here reflects the very significant number of users who really do like the traditional menu system and who wish to...

2 days ago by Moley on A tale of two distros: Ubuntu and Linux Mint
kevinmchapman

Er, no... It is an efficient means of finding the application/file/setting you need in one place. The icons are a simply a fallback for when you...

2 days ago by kevinmchapman on A tale of two distros: Ubuntu and Linux Mint
TerryRK

Isn't the provision of a text based search an admission by the developers that the mass of icons approach does not work? I don't need to use a...

2 days ago by TerryRK on A tale of two distros: Ubuntu and Linux Mint
kevinmchapman

"Unity and GNOME 3 both abandon the old text-based cascading menus in favour of a graphical icon-driven system." Point truly missed. Both use a...

2 days ago by kevinmchapman on A tale of two distros: Ubuntu and Linux Mint
TerryRK

whs001 - Thank you, I'm glad you liked the article. I absolutely agree with you on your first point. I should perhaps have made it clearer that...

2 days ago by TerryRK on A tale of two distros: Ubuntu and Linux Mint
Dennis Nilsson

If we allow corporate interest to dictate the way our government circumvents due process against foreign entities then we should accept the same...

2 days ago by Dennis Nilsson via Facebook on ACTA stumbles in Germany
GHar123

I totally dislike pirating of works, I fear that artists will be deterred from creating works if they think that they are going to get ripped off....

2 days ago by GHar123 on ACTA stumbles in Germany
JCB33

How dare film makers, artists or anybody that invests in creativity stop us pirating their works for free. I want to be able to walk into my local...

2 days ago by JCB33 on ACTA stumbles in Germany
Moley

@GrueMaster. I prefer horses for courses rather than one size fits all. I, and I suspect most other computer users, do not really wish to have...

2 days ago by Moley on A tale of two distros: Ubuntu and Linux Mint
greycynic

The product that scares me every time I have to use it is the Office 2007 version of Excel. The first bug that I found was applying the median...

2 days ago by greycynic on Ten flawed products that derail productivity
GrueMaster

Nice review and very informative. One thing I'd like to add (in reply to whs001's 1st question), the main reason to have the same interface from...

2 days ago by GrueMaster on A tale of two distros: Ubuntu and Linux Mint
Frederick Wrigley

I'be been using Mint 12 since the RC came out, and I am far more happy with the Cinnamon, the Mate, and, yes (with extensions), theGnome 3...

2 days ago by Frederick Wrigley via Facebook on A tale of two distros: Ubuntu and Linux Mint

Latest in IT Strategy

Heart of England NHS begins massive digitisation plan

Featured white papers

Value of a team: Five pillars to strengthen employee culture

Citrix Online

Value of a team: Five pillars to strengthen employee culture

This white paper explores how to define objectives for employees and clients and how the business can benefit from encouraging... Read more

Key trends driving global business resilience and risk

IBM

Key trends driving global business resilience and risk

This IBM research paper looks at how businesses are thinking more about business resilience by improving the ability to adapt to a continuously changing business... Read more

Cloud computing security: A practical guide

SunGard Availability Services

Cloud computing security: A practical guide

Cloud computing has been the belle of the IT ball, but can you trust it to keep data reliable and... Read more

Inside ZDNet UK

A tale of two distros: Ubuntu and Linux Mint

A tale of two distros: Ubuntu and Linux Mint

2012 Predictions: VCE FastPath, VI SAN Probe & Hadoop

2012 Predictions: VCE FastPath, VI SAN Probe & Hadoop

BlackBerry Bold 9790

BlackBerry Bold 9790

Make faster, smarter decisions using BI

Make faster, smarter decisions using BI

Ten factors that make Ubuntu 11.10 a hit

Ten factors that make Ubuntu 11.10 a hit

Toshiba Portégé Z830-10P Review

Toshiba Portégé Z830-10P Review

BT's archive: Pictures from the vault

BT's archive: Pictures from the vault