Asset Discovery Using DNS And SSL

Background There are times, more often than we’d like to admit, that we need to do asset discovery on our own organization (or, for you red teamers, other people’s!). This is actually simpler than you’d think, as long as you know the domains associated with the organization. Process First, create a text file containing the domains you’re interested in, one per line. Next, use OpenSSL to get a list of Subject Alternative Names (SANs) from any certificates present on the domains: [Read more...]

Solving The WHOIS GDPR Problem

Identifiers, not identities Recently, ICANN received a letter explaining that the WHOIS database, which contains registration information for all existing domain names on the Internet, will be in violation of the European General Data Protection Regulations (GDPR) law when it goes into effect on May 25, 2018. ICANN has responded, stating in essence that it has no solution to put in place prior to that date, and it needs an exemption, at least temporarily. [Read more...]

How To: Check For Symantec Certificates From the Command Line

Background Starting with Chrome 66 and Firefox 60, Symantec SSL certificates issued before June 1, 2016 will be distrusted. With Chrome 70 and Firefox 63, all Symantec SSL certs issued before December 1, 2017 will be distrusted. This creates a need to quickly scan for those certs. Use OpenSSL to check This is a fairly simple task with OpenSSL: $ timeout 1 openssl s_client -showcerts -connect my.domain.name:443 | openssl x509 -noout -startdate This will tell you the start date for a site’s certificate. [Read more...]