CVE-2021-22946: apple macos Missing Cryptographic Step

Vulnerability summary

CVE-2021-22946 is a high (CVSS 7.5) Missing Cryptographic Step vulnerability in apple macos. EPSS estimates a 4.54% chance of exploitation in the next 30 days, higher than 91.4% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 29-09-2021
   PublishedVulnerability first disclosed.
2. 14-10-2026
   Last modifiedVulnerability information updated.

Description

A user can tell curl >= 7.20.0 and <= 7.78.0 to require a successful upgrade to TLS when speaking to an IMAP, POP3 or FTP server (`--ssl-reqd` on the command line or`CURLOPT_USE_SSL` set to `CURLUSESSL_CONTROL` or `CURLUSESSL_ALL` withlibcurl). This requirement could be bypassed if the server would return a properly crafted but perfectly legitimate response.This flaw would then make curl silently continue its operations **withoutTLS** contrary to the instructions and expectations, exposing possibly sensitive data in clear text over the network.

• CWE-325Missing Cryptographic StepThe product does not implement a required step in a cryptographic algorithm, resulting in weaker encryption than advertised by the algorithm.
• CWE-319Cleartext Transmission of Sensitive InformationThe product transmits sensitive or security-critical data in cleartext in a communication channel that can be sniffed by unauthorized actors.