Authentication Bypass by Primary Weakness Affecting libcurl package, versions <0:8.0.1-1.amzn2.0.1

Note: Versions mentioned in the description apply only to the upstream libcurl package and not the libcurl package as distributed by Amazon-Linux. See How to fix? for Amazon-Linux:2 relevant fixed versions and status.

An authentication bypass vulnerability exists in libcurl <8.0.0 in the FTP connection reuse feature that can result in wrong credentials being used during subsequent transfers. Previously created connections are kept in a connection pool for reuse if they match the current setup. However, certain FTP settings such as CURLOPT_FTP_ACCOUNT, CURLOPT_FTP_ALTERNATIVE_TO_USER, CURLOPT_FTP_SSL_CCC, and CURLOPT_USE_SSL were not included in the configuration match checks, causing them to match too easily. This could lead to libcurl using the wrong credentials when performing a transfer, potentially allowing unauthorized access to sensitive information.

• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-27535
• https://hackerone.com/reports/1892780
• https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/36NBD5YLJXXEDZLDGNFCERWRYJQ6LAQW/
• https://lists.debian.org/debian-lts-announce/2023/04/msg00025.html
• https://security.netapp.com/advisory/ntap-20230420-0010/
• https://security.gentoo.org/glsa/202310-12
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/36NBD5YLJXXEDZLDGNFCERWRYJQ6LAQW/