Feeds

SSH an ill-managed mess says SSH author Tatu Ylonen

IETF draft a first step to new version

SANS - Survey on application security programs

Tatu Ylonen, author of the SSH protocol, isn't afraid of criticising his own work: he's calling for a new version of the Secure Shell to make it more manageable and get rid of the problem of undocumented rogue keys.

In this IETF Draft, Ylonen proposes a regime for key management, including key discovery, to overcome the problem. The draft, co-authored by NIST's Murugiah Souppaya and Secure IT's Greg Kent, proposes guidelines for “discovering, remediating, and continuously managing SSH user keys and other authentication credentials”.

The draft notes that there are often a great many more SSH keys in existence in an organisation than there are users – “hundreds of thousands, even over a million SSH keys authorising access have been found … [in] many large organizations. This is many times more than they have interactive users.”

Of course, having credentials wandering around loose in a company “present a real risk to information security”, the draft notes – and places a premium on finding out just what's out there.

This draft, open for comment until October, focuses on processes and key management, but according to Ylonen, a new SSH will be needed (the current version, SSH-2, dates from 2006).

Some of the recommendations in the draft appear to reveal a surprising state of affairs, at least among companies whose SSH implementations have been reviewed by Ylonen's company, SSH Security. The draft recommends:

  • Moving keys to protected locations;
  • Removing unused keys;
  • Associating authorised keys with a business process or application;
  • Removing keys for which no valid purpose can be found;
  • Rotating keys;
  • Restricting what can be done with each authorised key;
  • Establishing a process for approving new keys.

The list looks somewhat like what companies should already have been doing in managing their SSH access – but it's probable that someone configuring new kit finds it simpler to create such things ad-hoc. ®

Combat fraud and increase customer satisfaction

More from The Register

next story
Parent gabfest Mumsnet hit by SSL bug: My heart bleeds, grins hacker
Natter-board tells middle-class Britain to purée its passwords
Obama allows NSA to exploit 0-days: report
If the spooks say they need it, they get it
Web data BLEEDOUT: Users to feel the pain as Heartbleed bug revealed
Vendors and ISPs have work to do updating firmware - if it's possible to fix this
Samsung Galaxy S5 fingerprint scanner hacked in just 4 DAYS
Sammy's newbie cooked slower than iPhone, also costs more to build
Mounties always get their man: Heartbleed 'hacker', 19, CUFFED
Canadian teen accused of raiding tax computers using OpenSSL bug
Snowden-inspired crypto-email service Lavaboom launches
German service pays tribute to Lavabit
One year on: diplomatic fail as Chinese APT gangs get back to work
Mandiant says past 12 months shows Beijing won't call off its hackers
prev story

Whitepapers

Designing a defence for mobile apps
In this whitepaper learn the various considerations for defending mobile applications; from the mobile application architecture itself to the myriad testing technologies needed to properly assess mobile applications risk.
3 Big data security analytics techniques
Applying these Big Data security analytics techniques can help you make your business safer by detecting attacks early, before significant damage is done.
Five 3D headsets to be won!
We were so impressed by the Durovis Dive headset we’ve asked the company to give some away to Reg readers.
The benefits of software based PBX
Why you should break free from your proprietary PBX and how to leverage your existing server hardware.
Securing web applications made simple and scalable
In this whitepaper learn how automated security testing can provide a simple and scalable way to protect your web applications.