Perimeter
11/8/2012
10:59 AM
Dark Reading
Dark Reading
Products and Releases
Connect Directly
RSS
E-Mail
50%
50%

M3AAWG Issues DKIM New Best Practices In Wake of Disclosed Key Length Vulnerability

M3AAWG is calling on business enterprises to replace previously secure 512- and 768-bit verification keys with 1024-bit and higher encryption

San Francisco, Nov. 6, 2012 – With the recently revealed ability to spoof email from companies that are using an outdated, weak encryption key to authenticate their email, the Messaging, Malware and Mobile Anti-Abuse Working Group is urging companies to adjust their DKIM processes immediately to improve end-user safeguards and today issued new best practices that specifically address the vulnerability. M3AAWG is calling on business enterprises to replace previously secure 512- and 768-bit verification keys with 1024-bit and higher encryption, among other recommendations to better validate the authenticity of who is sending an email.

"We've developed a short, succinct paper that explains the relatively simple and immediate steps large-scale senders can take to safeguard their brands in response to recent concerns about some levels of key encryption and usage. Technology is advancing, and to keep pace with hackers, the industry needs to revisit its practices in light of their expanding capabilities. We want to get the word out on the quick changes companies can make to protect consumers and their brands against this issue," Chris Roosenraad, M3AAWG Co-Chairman said.

"M3AAWG Best Practices for Implementing DKIM To Avoid Key Length Vulnerability," details the technical steps that address the current vulnerabilities and is available in the Published Documents section of the organization's website at www.m3aawg.org/published-documents. The recommendations include:

· Updating to a minimum 1024-bit key length. Shorter keys can be cracked in 72 hours using inexpensive cloud services

· Rotating keys quarterly

· Setting signatures to expire after the current key rotation period and revoking old keys in the DNS

· Using the key test mode only for a short time period and revoking the test key after the ramp-up

· Implementing DMARC in monitoring mode and using DNS to monitor how frequently keys are queried. DMARC (Domain-based Message Authentication, Reporting and Conformance) is another standard often used in conjunction with DKIM

· Using DKIM rather than Domain Keys, which is a depreciated protocol

· Working with any third parties hired to send a company's email to ensure they are adhering to these best practices

DKIM is a widely accepted standard used by businesses, governmental agencies, large email provider services and other entities that allows an organization to claim responsibility for sending a message in a way that can be validated by a recipient. For example, email services, such as AOL, Gmail and Yahoo, and commercial brands implement the standard as part of their messaging protocol. It includes an encrypted key in the message headers that ISPs and other receivers use to verify the message actually was sent by the referenced company.

Implementing DKIM makes it more difficult for criminals to forge illegitimate emails that are made to look like they came from a recognized company, a ruse that is often used to steal personal identity information from unsuspecting users. In late October, Wired journalist Kim Zetter reported that many companies were using weak encryption keys and other questionable practices as part of their DKIM implementation that could expose their email to this potential spoofing by cybercriminals.

About the Messaging, Malware and Mobile Anti-Abuse Working Group (M3AAWG)

The Messaging, Malware and Mobile Anti-Abuse Working Group (M3AAWG) is where the industry comes together to work against bots, malware, spam, viruses, denial-of-service attacks and other online exploitation. M3AAWG (www.M3AAWG.org) represents more than one billion mailboxes from some of the largest network operators worldwide. It leverages the depth and experience of its global membership to tackle abuse on existing networks and new emerging services through technology, collaboration and public policy. It also works to educate global policy makers on the technical and operational issues related to online abuse and messaging. Headquartered in San Francisco, Calif., M3AAWG is an open forum driven by market needs and supported by major network operators and messaging providers.

Comment  | 
Print  | 
More Insights
Register for Dark Reading Newsletters
Partner Perspectives
What's This?
In a digital world inundated with advanced security threats, Intel Security seeks to transform how we live and work to keep our information secure. Through hardware and software development, Intel Security delivers robust solutions that integrate security into every layer of every digital device. In combining the security expertise of McAfee with the innovation, performance, and trust of Intel, this vision becomes a reality.

As we rely on technology to enhance our everyday and business life, we must too consider the security of the intellectual property and confidential data that is housed on these devices. As we increase the number of devices we use, we increase the number of gateways and opportunity for security threats. Intel Security takes the “security connected” approach to ensure that every device is secure, and that all security solutions are seamlessly integrated.
Featured Writers
White Papers
Cartoon
Current Issue
Dark Reading's October Tech Digest
Fast data analysis can stymie attacks and strengthen enterprise security. Does your team have the data smarts?
Flash Poll
Title Partner’s Role in Perimeter Security
Title Partner’s Role in Perimeter Security
Considering how prevalent third-party attacks are, we need to ask hard questions about how partners and suppliers are safeguarding systems and data.
Video
Slideshows
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2013-3304
Published: 2014-10-30
Directory traversal vulnerability in Dell EqualLogic PS4000 with firmware 6.0 allows remote attackers to read arbitrary files via a .. (dot dot) in the default URI.

CVE-2013-7409
Published: 2014-10-30
Buffer overflow in ALLPlayer 5.6.2 through 5.8.1 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via a long string in a .m3u (playlist) file.

CVE-2014-3446
Published: 2014-10-30
SQL injection vulnerability in wcm/system/pages/admin/getnode.aspx in BSS Continuity CMS 4.2.22640.0 allows remote attackers to execute arbitrary SQL commands via the nodeid parameter.

CVE-2014-3584
Published: 2014-10-30
The SamlHeaderInHandler in Apache CXF before 2.6.11, 2.7.x before 2.7.8, and 3.0.x before 3.0.1 allows remote attackers to cause a denial of service (infinite loop) via a crafted SAML token in the authorization header of a request to a JAX-RS service.

CVE-2014-3623
Published: 2014-10-30
Apache WSS4J before 1.6.17 and 2.x before 2.0.2, as used in Apache CXF 2.7.x before 2.7.13 and 3.0.x before 3.0.2, when using TransportBinding, does properly enforce the SAML SubjectConfirmation method security semantics, which allows remote attackers to conduct spoofing attacks via unspecified vect...

Best of the Web
Dark Reading Radio
Archived Dark Reading Radio
Follow Dark Reading editors into the field as they talk with noted experts from the security world.