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

7/9/2008
06:59 PM
Connect Directly
Google+
LinkedIn
Twitter
RSS
E-Mail
50%
50%

Security Community Cooperates To Fix 'DNS Poisoning'

Armed with knowledge of DNS transaction IDs, an attacker could reroute requests for certain Web sites to Web sites of his or her choosing or hijack e-mail.

US-CERT, the government's cyber security arm, on Tuesday warned of a serious weakness in the Domain Name System (DNS) protocol that could be used to send Internet users to malicious sites.

In an unusual move that reflects the seriousness of the security flaw, news of the vulnerability was delayed for months to allow software vendors like Microsoft, Cisco, and Sun -- more than 80 are affected -- to release coordinated fixes.

As part of its monthly patch schedule, Microsoft on Tuesday fixed the DNS flaw in Windows with patch MS08-037, "Vulnerabilities in DNS Could Allow Spoofing."

Amol Sarwate, manager of vulnerability labs at Qualys, considers the vulnerability to be significant. "I wouldn't characterize it as an end of the world scenario but it is a very important vulnerability," he said.

While details about the vulnerability and how to exploit it have been deliberately withheld, Sarwate said that the issue appears to be that the transaction ID generated in a DNS request -- querying a DNS server to link an IP address with an Internet domain name -- is insufficiently random to avoid being guessed by a knowledgeable attacker.

Armed with knowledge of DNS transaction IDs, an attacker could reroute requests for certain Web sites to Web sites of his or her choosing or hijack e-mail. The technique is called DNS poisoning.

US-CERT says that "per-query source port randomization" can mitigate the risk posed by the vulnerability.

"The effect of the vulnerability, if it was ever exploited, is enormous," explained Jeff Kalwerisky, chief security evangelist of Alpha Software. "Someone who exploited the vulnerability would be able to reroute every single transaction in your computer."

"The good news is that for the average user on the desktop, if you've got automated patching on Windows, you've got the patch already," said Kalwerisky. "The hard part is a large corporation with multiple DNS servers and routers and switchers."

Kalwerisky advises patching as soon as possible.

Dan Kaminsky of IO Active, the researcher who discovered the flaw, has posted an online vulnerability checker at doxpara.com. And if checking one's site can be done so easily, expect cyber criminals to scout the Net for vulnerable machines just as soon as they figure out how the flaw can be exploited.

Kalwerisky said that the way the vulnerability has been handled shows the security community can work together effectively. "Dan has proved the utter value of independent secure researchers," he said "Security should not be locked up in Microsoft or other software houses."

Kaminsky is scheduled to disclose details about the vulnerability at the Black Hat Conference in Las Vegas on August 6th.

 

Recommended Reading:

Comment  | 
Print  | 
More Insights
Comments
Threaded  |  Newest First  |  Oldest First
COVID-19: Latest Security News & Commentary
Dark Reading Staff 7/14/2020
Omdia Research Launches Page on Dark Reading
Tim Wilson, Editor in Chief, Dark Reading 7/9/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon
Current Issue
Special Report: Computing's New Normal, a Dark Reading Perspective
This special report examines how IT security organizations have adapted to the "new normal" of computing and what the long-term effects will be. Read it and get a unique set of perspectives on issues ranging from new threats & vulnerabilities as a result of remote working to how enterprise security strategy will be affected long term.
Flash Poll
The Threat from the Internetand What Your Organization Can Do About It
The Threat from the Internetand What Your Organization Can Do About It
This report describes some of the latest attacks and threats emanating from the Internet, as well as advice and tips on how your organization can mitigate those threats before they affect your business. Download it today!
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2020-10287
PUBLISHED: 2020-07-15
The IRC5 family with UAS service enabled comes by default with credentials that can be found on publicly available manuals. ABB considers this a well documented functionality that helps customer set up however, out of our research, we found multiple production systems running these exact default cre...
CVE-2020-10288
PUBLISHED: 2020-07-15
IRC5 exposes an ftp server (port 21). Upon attempting to gain access you are challenged with a request of username and password, however you can input whatever you like. As long as the field isn't empty it will be accepted.
CVE-2020-15780
PUBLISHED: 2020-07-15
An issue was discovered in drivers/acpi/acpi_configfs.c in the Linux kernel before 5.7.7. Injection of malicious ACPI tables via configfs could be used by attackers to bypass lockdown and secure boot restrictions, aka CID-75b0cea7bf30.
CVE-2019-17639
PUBLISHED: 2020-07-15
In Eclipse OpenJ9 prior to version 0.21 on Power platforms, calling the System.arraycopy method with a length longer than the length of the source or destination array can, in certain specially crafted code patterns, cause the current method to return prematurely with an undefined return value. This...
CVE-2019-20908
PUBLISHED: 2020-07-15
An issue was discovered in drivers/firmware/efi/efi.c in the Linux kernel before 5.4. Incorrect access permissions for the efivar_ssdt ACPI variable could be used by attackers to bypass lockdown or secure boot restrictions, aka CID-1957a85b0032.