CVE-2023-23914

Name of the Vulnerable Software and Affected Versions curl versions prior to 7.88.0

Description A cleartext transmission of sensitive information issue exists in curl that could cause HSTS functionality to fail when multiple URLs are requested serially. Using its HSTS support, curl can be instructed to use HTTPS instead of using an insecure clear-text HTTP step even when HTTP is provided in the URL. However, this HSTS mechanism would be ignored by subsequent transfers when done on the same command line because the state would not be properly carried on. The issue can be reproduced by requesting multiple URLs serially, such as https://curl.se followed by http://curl.se, where the second URL fails to take advantage of the HSTS information returned by the first URL.

Recommendations For versions prior to 7.88.0, update to version 7.88.0 or later to resolve the issue. As a temporary workaround, consider avoiding the use of multiple URLs in the same command line to minimize the risk of exploitation. Restrict access to sensitive information and use HTTPS instead of HTTP to reduce the risk of cleartext transmission of sensitive information.