Feeds

Siemens fixes SCADA holes found by hacker

Vulns were kept quiet at request of manufacturer

Securing Web Applications Made Simple and Scalable

Siemens has patched security vulnerabilities in its widely used Simatic S7 industrial computer system that made it possible for attackers to disrupt or sabotage operations at gas refineries, chemical plants and other critical facilities.

In an advisory (PDF) issued on Friday, the Industrial Control Systems Cyber Emergency Response Team said the Siemens update fixed a “portion” of the vulnerabilities discovered in the S7-1200 PLC, or programmable logic controller, by NSS Labs researcher Dillon Beresford. Last month, he and a colleague cancelled a scheduled talk about critical vulnerabilities in the PLC following requests by the German manufacturer and officials from the US Department of Homeland Security.

A separate advisory issued by Siemens said the updated firmware fixed two vulnerabilities.

The first enabled so-called replay attacks, in which digital communications between engineering software and the controller is recorded and then transmitted again at a later time. By capturing the data, attackers could use it later to carry out sensitive functions not specifically authorized. A mitigating caveat: the replayed data could be used only against the same controller that received the initial instructions. What's more, the attack would work only when an attacker had network access to the targeted PLC.

A second vulnerability allowed attackers to shut down a controller by overloading the communications it receives.

“The latest firmware update for the S7-1200 will offer corrective action for enhancing protection against replay attacks as well as increased stability when facing the above-mentioned denial-of-service scenario,” the Siemens advisory stated.

Beresford has stressed that he voluntarily canceled his talk but went on to blast Siemens engineers for downplaying the severity of his findings. He is scheduled to speak about the security of the PLCs in August during a briefing at the Black Hat security conference in Las Vegas. ®

The smart choice: opportunity from uncertainty

More from The Register

next story
Mozilla fixes CRITICAL security holes in Firefox, urges v31 upgrade
Misc memory hazards 'could be exploited' - and guess what, one's a Javascript vuln
Manic malware Mayhem spreads through Linux, FreeBSD web servers
And how Google could cripple infection rate in a second
How long is too long to wait for a security fix?
Synology finally patches OpenSSL bugs in Trevor's NAS
Don't look, Snowden: Security biz chases Tails with zero-day flaws alert
Exodus vows not to sell secrets of whistleblower's favorite OS
Roll out the welcome mat to hackers and crackers
Security chap pens guide to bug bounty programs that won't fail like Yahoo!'s
HIDDEN packet sniffer spy tech in MILLIONS of iPhones, iPads – expert
Don't panic though – Apple's backdoor is not wide open to all, guru tells us
Researcher sat on critical IE bugs for THREE YEARS
VUPEN waited for Pwn2Own cash while IE's sandbox leaked
prev story

Whitepapers

Top three mobile application threats
Prevent sensitive data leakage over insecure channels or stolen mobile devices.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Boost IT visibility and business value
How building a great service catalog relieves pressure points and demonstrates the value of IT service management.
Designing a Defense for Mobile Applications
Learn about the various considerations for defending mobile applications - from the application architecture itself to the myriad testing technologies.
Build a business case: developing custom apps
Learn how to maximize the value of custom applications by accelerating and simplifying their development.