Feeds

Brits pound OpenSSL bugs

Abstract thinking

  • alert
  • submit to reddit

Choosing a cloud hosting partner with confidence

Research by the U.K. government into a once-overlooked class of software vulnerability has surfaced three new security holes in the ubiquitous OpenSSL software package, according to advisories released Tuesday.

All versions of OpenSSL up to and including 0.9.6j and 0.9.7b, and all versions of SSLeay, are open to the attacks: two of the holes can crash the software; a third could lead to an attacker gaining control over vulnerable machines, although the latter scenario remains undemonstrated, according to an advisory from the OpenSSL Project, the collaborative effort that maintains the open-source package.

The vulnerabilities are in the way OpenSSL processes a data format called Abstract Syntax Notation One (ASN.1) -- an internationally recognized standard for coding and transmitting complex data structures, and a building block of the digital certificates that make SSL work.

ASN.1 security commanded high-level U.S. government interest last year after researchers at the Oulu University Secure Programming Group in Finland exploited the format in a novel attack technique that proved effective against dozens of implementations of the Simple Network Management Protocol (SNMP) -- the Internet's standard language for monitoring and controlling routers, switches and other devices. The research forced nearly two hundred companies to evaluate, and in some cases patch, products that used SNMP.

The Oulu research involved systematically flinging a wide variety of intentionally-malformed data at the servers, deliberately violating the rules of ASN.1 in a number of ways that programmers hadn't anticipated: lying about the amount of data being transmitted in a particular field, for example. Where coders didn't plan for illegally-formatted messages, the vulnerable system would crash, or in some cases allow an attacker to overflow an internal buffer and execute malicious instructions on the target machine.

"It's sort of the Monte Carlo approach, because that's the easiest way to deal with ASN.1," says Bruce Schneier, CTO at Counterpane Internet Security Inc. "You really can't look at it systematically because it's so opaque."

U.S. government and industry officials became gravely concerned that the same attack method might be equally effective against other networks and protocols relying on ASN.1, a long list of "critical infrastructures" that includes telephone switching networks, parcel delivery tracking systems, credit card verification networks, and electric utility SCADA systems.

A government working group was formed to tackle the problem, and then-cybersecurity czar Richard Clarke, and his deputy Howard Schmidt, personally briefed President Bush on the issue, Clarke said at the time.

But Tuesday it was a parallel effort by the U.K. government's National Infrastructure Security Coordination Center (NISCC) that bore fruit. Building on the Oulu University's work, the center's been performing and funding its own research into ASN.1 vulnerabilities that could affect critical infrastructures. In the process, NISCC researchers developed a customized test suite that they provided to the OpenSSL Project -- primarily based in the U.K. and Germany -- which used it to find the three holes, according to advisories from both groups.

The only thing surprising is that there haven't been more ASN.1 implementation holes made public in other programs, says Schneier. "I've always thought there should be more, but my guess is that they're just hard to find."

The OpenSSL holes are triggered by delivering malformed ASN.1 data to the vulnerable server through a client certificate-- but another bug in the package makes it effective even against SSL/TLS servers that haven't enabled client authentication. New versions of the software are available that close the holes.

Copyright © 2003,

Internet Security Threat Report 2014

More from The Register

next story
FYI: OS X Yosemite's Spotlight tells Apple EVERYTHING you're looking for
It's on by default – didn't you read the small print?
Russian hackers exploit 'Sandworm' bug 'to spy on NATO, EU PCs'
Fix imminent from Microsoft for Vista, Server 2008, other stuff
Edward who? GCHQ boss dodges Snowden topic during last speech
UK spies would rather 'walk' than do 'mass surveillance'
Microsoft pulls another dodgy patch
Redmond makes a hash of hashing add-on
NOT OK GOOGLE: Android images can conceal code
It's been fixed, but hordes won't have applied the upgrade
Apple grapple: Congress kills FBI's Cupertino crypto kybosh plan
Encryption would lead us all into a 'dark place', claim G-Men
DEATH by PowerPoint: Microsoft warns of 0-day attack hidden in slides
Might put out patch in update, might chuck it out sooner
prev story

Whitepapers

Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Why and how to choose the right cloud vendor
The benefits of cloud-based storage in your processes. Eliminate onsite, disk-based backup and archiving in favor of cloud-based data protection.
Three 1TB solid state scorchers up for grabs
Big SSDs can be expensive but think big and think free because you could be the lucky winner of one of three 1TB Samsung SSD 840 EVO drives that we’re giving away worth over £300 apiece.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.