CVE-2021-22947 log

Severity Medium
Remote Yes
Type Man-in-the-middle
A STARTTLS protocol injection flaw via man-in-the-middle was found in curl before 7.79.0. 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 upgrade to TLS but not flush the in-queue of cached responses and instead use and trust the responses it got before the TLS handshake as if they were authenticated.
Using this flaw, it allows a Man-In-The-Middle attacker to first inject the fake responses, then pass-through the TLS traffic from the legitimate server and trick curl into sending data back to the user thinking the attacker's injected data comes from the TLS-protected server.
Over POP3 and IMAP an attacker can inject fake response data.
Group Package Affected Fixed Severity Status Ticket
AVG-2389 lib32-libcurl-gnutls 7.78.0-1 7.79.0-1 High Fixed
AVG-2388 libcurl-gnutls 7.78.0-1 7.79.0-1 High Fixed
AVG-2387 lib32-libcurl-compat 7.78.0-1 7.79.0-1 High Fixed
AVG-2386 libcurl-compat 7.78.0-1 7.79.0-1 High Fixed
AVG-2385 lib32-curl 7.78.0-1 7.79.0-1 High Fixed
AVG-2384 curl 7.78.0-1 7.79.0-1 High Fixed