Mozilla blocks Dutch Govt DigiNotar SSL certificates

DigiNotar’s intermediaries issued fraudulent certificates too, says director of Firefox engineering.

DigiNotar’s intermediaries issued fraudulent certificates too, says director of Firefox engineering.

The impact of the breach of Dutch Secure Sockets Layer (SSL) certificate authority (CA) DigiNotar has widened as Dutch authorities confirm its own certificate program was compromised in the attack, likely meaning a massive clean up job for its websites.

Mozilla extended its ban on DigiNotar certificates over the weekend to those issued by the company under the Dutch government’s certificate authority program, PKYoverheid.

At the request of the Dutch Government Mozilla had exempted from DigiNotar certificates issued under PKIoverheid from its DigiNotar blacklist because the nation’s computer emergency response team (GovCERT) assured Mozilla this particular system was not compromised.

“The Dutch government has since audited DigiNotar’s performance and rescinded this assessment,” Mozilla’s director of Firefox engineering Jonathan Nightingale said on Friday.

“We are now removing the exemption for these certificates, meaning that all DigiNotar certificates will be untrusted by Mozilla products.”

Nightingale added that the attackers had issued certificates from another DigiNotar intermediary without proper logging.

“It is therefore impossible for us to know how many fraudulent certificates exist, or which sites are targeted,” he said.

He emphasised that the attacks using fraudulent SSL certificates were “not theoretical” and that DigiNotar had confirmed that over 200 certificates were fraudulently issued against 20 different domains.

“We have received multiple reports of these certificates being used in the wild,” he said.

Dutch security firm Madison Gurka claimed last week that about 200 were generated by the attackers, including ones valid for, and

DigiNotar has been widely criticised for failing to disclose the breach until six weeks after it discovered it and for being unclear about the true extent of potential damage.

“The integrity of the SSL system cannot be maintained in secrecy. Incidents like this one demonstrate the need for active, immediate and comprehensive communication between CAs and software vendors to keep our collective users safe online,” said Nightingale.

The discovery that DigiNotar’s processes under the Dutch Government’s scheme were compromised will cause it big headaches, according to Kaspersky Lab antivirus researcher Roel Schouwebberg.

“A lot of Dutch government sites and services are going to be affected by the revocation. Clean up is going to be painful,” he said.
“The Dutch government has used DigiNotar as an intermediary CA in quite a lot of cases.”

Slideshows you may be interested in:

Most Influential Security Novels 

10 scariest hacks from Black Hat and Defcon 

Join the CSO newsletter!

Error: Please check your email address.

Tags breachMadison Gurka(SSL) certificate authoritygovcertPKYoverheidnewsDigiNotarkaspersky labmozillacaYahoosecurityRoel Schouwebberg

More about CA TechnologiesCERT AustraliaKasperskyKasperskyMozillaYahoo

Show Comments

Featured Whitepapers

Editor's Recommendations

Solution Centres

Stories by Liam Tung

Latest Videos

  • 150x50

    CSO Webinar: The Human Factor - Your people are your biggest security weakness

    ​Speakers: David Lacey, Researcher and former CISO Royal Mail David Turner - Global Risk Management Expert Mark Guntrip - Group Manager, Email Protection, Proofpoint

    Play Video

  • 150x50

    CSO Webinar: Current ransomware defences are failing – but machine learning can drive a more proactive solution

    Speakers • Ty Miller, Director, Threat Intelligence • Mark Gregory, Leader, Network Engineering Research Group, RMIT • Jeff Lanza, Retired FBI Agent (USA) • Andy Solterbeck, VP Asia Pacific, Cylance • David Braue, CSO MC/Moderator What to expect: ​Hear from industry experts on the local and global ransomware threat landscape. Explore a new approach to dealing with ransomware using machine-learning techniques and by thinking about the problem in a fundamentally different way. Apply techniques for gathering insight into ransomware behaviour and find out what elements must go into a truly effective ransomware defence. Get a first-hand look at how ransomware actually works in practice, and how machine-learning techniques can pick up on its activities long before your employees do.

    Play Video

  • 150x50

    CSO Webinar: Get real about metadata to avoid a false sense of security

    Speakers: • Anthony Caruana – CSO MC and moderator • Ian Farquhar, Worldwide Virtual Security Team Lead, Gigamon • John Lindsay, Former CTO, iiNet • Skeeve Stevens, Futurist, Future Sumo • David Vaile - Vice chair of APF, Co-Convenor of the Cyberspace Law And Policy Community, UNSW Law Faculty This webinar covers: - A 101 on metadata - what it is and how to use it - Insight into a typical attack, what happens and what we would find when looking into the metadata - How to collect metadata, use this to detect attacks and get greater insight into how you can use this to protect your organisation - Learn how much raw data and metadata to retain and how long for - Get a reality check on how you're using your metadata and if this is enough to secure your organisation

    Play Video

  • 150x50

    CSO Webinar: How banking trojans work and how you can stop them

    CSO Webinar: How banking trojans work and how you can stop them Featuring: • John Baird, Director of Global Technology Production, Deutsche Bank • Samantha Macleod, GM Cyber Security, ME Bank • Sherrod DeGrippo, Director of Emerging Threats, Proofpoint (USA)

    Play Video

  • 150x50

    IDG Live Webinar:The right collaboration strategy will help your business take flight

    Speakers - Mike Harris, Engineering Services Manager, Jetstar - Christopher Johnson, IT Director APAC, 20th Century Fox - Brent Maxwell, Director of Information Systems, THE ICONIC - IDG MC/Moderator Anthony Caruana

    Play Video

More videos

Blog Posts