This an unofficial and not-so-beautiful translation by Bits of Freedom of Diginotar's messages to its customers regarding the breach of its security. The original text, which appears to be Dutch translated partly from English, can be found here:

http://diginotar.nl/Actueel/tabid/264/articleType/ArticleView/articleId/327/Default.aspx


Messages have appeared on the internet regarding DigiNotar certificates which are not being trusted by the Browsers anymore (Microsoft Internet Explorer, Mozilla, Firefox, Chrome).

This follows from a hacker attack on the computers of Diginotar, which took place mid July this year.

DigiNotar has discovered this attack and taken comprehensive countermeasures. We used our own expertise, as well as external IT security experts which have performed an extensive investigation into how this attack was possible.

It appears that certificates have erroneously come into circulation from a subRoot (the Public Root 2025). From the performed investigation, it turns out that that this only concerns SSL certificates and EVSSL certificates which have been issued under this subRoot.

Other Roots have remained untouched. This applies in particular to the root from which PKIoverheid certificates are issued and the subRoot from which the DigiNotar qualified certificates are issued. Meanwhile, DigiNotar revoked all certificates which the investigation identified as issued erroneously, and these are thus not used anymore.

Unfortunately it turns out that there was still a certificate (in the name of Google.com) in circulation. This meanwhile has also been revoked. As far as we know, this certificate has been abused in Iran against users in Iran.

DigiNotar has asked the independent firm Fox-IT, specializing in IT security, to again examine its systems in order to exclude all future risks as much as possible. The results of this investigation will be
made public as soon as possible.

Implications for daily practice

Currently, pending this investigation, Browser suppliers have reacted differently to the statements regarding the confidence in the DigiNotar Roots in the Browser. One Browser supplier indicates that only the "bad" 2025 Public Root no longer is to be trusted, while the other states that other certificates from other Roots are not to be trusted. The latter conclusion is thus unjustified. DigiNotar is committed to remove any misunderstandings as quickly as possible.

The browser vendors have already indicated that the security of the PKIOverheid Root and thus all PKIOverheid Root Certificates is not at stake. Users of SSL certificates, can depending on the method which the browsersupplier uses, be confronted with a message that the certificate is not to be trusted. This is incorrect in 99.9% of the cases: the certificate can be trusted. This can be indicated manually by the user in the browser, similar to certificates of issuers whose Root is not included in the Browser (see for the method the FAQ on our website).

Users of other types of certificates will not normally be affected by the incident.

DigiNotar offers all holders of SSL and EVSSL certificates an option to return their certificates in exchange for PKIoverheid (EV) SSL certificates in order to reduce the inconvenience to the users to a minimum. When exchanging the certificates, the conditions for issuing PKIoverheid certificates should be taken into consideration. The exchange is of course without costs.