Pretty Good Privacy Flaw Reported

The security flaw centers on PGP's key recovery system, allowing someone to gain escrow capabilities over a sender's message, according to industry analysts.

PGP, a business unit of Network Associates (NAI), last week issued a public "regret" for the flaw on its Web site. The company is offering via download patches and new 6.5x freeware releases to fix the bug, according to Mike Wallach, president of PGP's security division.

Wallach described the potential PGP attack as "esoteric" and extremely difficult to pull off. He said the company has not found any user with compromised data because of the publicized flaw. The affected source code was written by PGP creator Phillip Zimmerman more than three years ago, before the company was acquired by NAI.

"This is the reason we have always submitted our source code for peer review. We want and expect people to find vulnerabilities so we can fix them," Wallach said.

Key recovery is a mechanism for third parties, such as law enforcement agencies, to unscramble encrypted information. In PGP, a user encrypts data with their private key, which is then decrypted by a public key.

PGP uses an Additional Decryption Key (ADK) that works in parallel with the user's private key to allow for third party decryption of data. Although use of ADKs is not required, the capability is in place with versions of PGP. Because the ADK does not use a digital signature, holders of non-signed ADKs -- which can be created without the real user's knowledge -- can intercept the message, said Shawn Hernan, team leader for vulnerability handling at the CERT (Computer Emergency Response Team) Coordination Center.

"If a sender of a message isn't paying attention, which is easy to do, it's possible to encrypt not only to the key you intended to, but also to the key of an intruder's choosing under some circumstances," Hernan said.

Charging into a pressure-intense security market, PGP is guilty of being a bit "too liberal" for keys it will encrypt to, Hernan added. "The problem here was just a simple oversight," he said. "The fix to the code was just a simple design. More rigorous design or more rigorous testing probably would have caught it."

The PGP vulnerability, which was discovered by German researcher Ralf Senderek, brings to light criticism of key escrow implementation that is often deployed at the corporate level, said Brad Arkin, a manager at Reliable Software Technologies' security group.

"Key escrow, at an executive-summary level, looks good on paper," Arkin said. "But as you introduce more complexity, it becomes more difficult to manage." It is a difficult and complicated process to decide who would have control over a digital signature in ADK, he added.

Join the newsletter!

Or

Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.
Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.
Show Comments

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Tom Pope

Dynabook Portégé X30L-G

Ultimately this laptop has achieved everything I would hope for in a laptop for work, while fitting that into a form factor and weight that is remarkable.

Tom Sellers

MSI P65

This smart laptop was enjoyable to use and great to work on – creating content was super simple.

Lolita Wang

MSI GT76

It really doesn’t get more “gaming laptop” than this.

Jack Jeffries

MSI GS75

As the Maserati or BMW of laptops, it would fit perfectly in the hands of a professional needing firepower under the hood, sophistication and class on the surface, and gaming prowess (sports mode if you will) in between.

Taylor Carr

MSI PS63

The MSI PS63 is an amazing laptop and I would definitely consider buying one in the future.

Christopher Low

Brother RJ-4230B

This small mobile printer is exactly what I need for invoicing and other jobs such as sending fellow tradesman details or step-by-step instructions that I can easily print off from my phone or the Web.

Featured Content

Product Launch Showcase

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?