TLS
3 articles with this tag
What is public-key cryptography: encrypting and signing with a key pair
Public-key crypto uses a 'public key' (safe to hand out) and a 'private key' (held only by the owner). Anything encrypted with the public key can only be decrypted by the matching private key, and a signature made with the private key can be verified with the public key. That asymmetry underpins TLS (HTTPS) key exchange, digital signatures, and passkeys. Defenses: don't roll your own crypto (use standard protocols and proven libraries), protect and be able to revoke the private key, and keep key length and algorithms current.
What is OpenSSL? The library that handles HTTPS encryption, and how to keep it safe
OpenSSL = the open-source library that powers HTTPS (TLS/SSL) and crypto. Most people never write it directly — they inherit it via the web server, OS, or language runtime. That's why one bug has an enormous impact (Heartbleed is the classic case). Defense: know which OpenSSL your stack uses, don't run EOL versions, include foundational libraries in CVE monitoring, and patch promptly. Even the certificates this site serves run crypto through an OpenSSL-family implementation underneath.
Heartbleed (CVE-2014-0160) — an OpenSSL bug that leaked server memory
OpenSSL's memory over-read could leak private keys and sessions. The cause: the server trusted a claimed length and read adjacent memory. The lesson: act as if it all leaked (re-issue certificates, rotate all secrets), monitor widely used base libraries, and value memory safety.