read vulnerability.
Heartbleed was a vulnerability in OpenSSL, a widely-used toolkit
written in C
that implements the cryptographic protocol Secure Sockets Layer
(SSL) and its successor the Transport Layer Security (TLS).
Heartbleed affected a huge number of popular websites, including
Google, YouTube, Yahoo!, Pinterest, Blogspot, Instagram, Tumblr,
Reddit, Netflix, Stack Overflow, Slate, GitHub, Yelp, Etsy, the
U.S. Postal Service (USPS), Blogger, Dropbox, Wikipedia, and the
Washington Post.
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