curl: Server responses received before STARTTLS processed after TLS handshake

A flaw was found in curl. The flaw lies in how curl handles cached or pipelined responses that it receives from either a IMAP, POP3, SMTP or FTP server before the TLS upgrade using STARTTLS. In such a scenario curl even after upgrading to TLS would trust these cached responses treating them as...

Medium: curl

Issue Overview: A flaw was found in libcurl. When sending data to an MQTT server could in some situations lead to libcurl using already freed memory and then try to free it again. The highest threat from this vulnerability is to data confidentiality as well as system availability. CVE-2021-22945 ...

STARTTLS protocol injection via MITM

When curl connects to an IMAP, POP3, SMTP or FTP server to exchange data securely using STARTTLS to upgrade the connection to TLS level, the server can still respond and send back multiple responses before the TLS upgrade. Such multiple pipelined responses are cached by curl. curl would then...