In the last couple of years, the number of software vulnerabilities and corresponding incidents increased significantly. In order to stay up-to-date about these new emerging threats, organizations have demonstrated an increased willingness to exchange information and knowledge about vulnerabilities, threats, incidents and countermeasures. Apart from dedicated sharing platforms or databases, information on vulnerabilities is frequently shared on Twitter and other social media platforms. So far, little is known about the obtainable time advantage of vulnerability information shared on social media platforms. To close this gap, we identified 709,880 relevant Tweets and subsequently analyzed them. We found that information with high relevance for affected organizations is shared on Twitter often long before any official announcement or patch has been made available by vendors. Twitter is used as a crowdsourcing platform by security experts aggregating vulnerability information and referencing a multitude of public available webpages in their Tweets. Vulnerability information shared on Twitter can improve organizations reaction to newly discovered vulnerabilities and therefore help mitigating threats.