vulnerability

Amazon Linux 2023: CVE-2023-27536: Medium priority package update for curl

Severity
7
CVSS
(AV:N/AC:M/Au:N/C:C/I:N/A:N)
Published
Mar 20, 2023
Added
Feb 17, 2025
Modified
Jul 4, 2025

Description

An authentication bypass vulnerability exists libcurl <8.0.0 in the connection reuse feature which can reuse previously established connections with incorrect user permissions due to a failure to check for changes in the CURLOPT_GSSAPI_DELEGATION option. This vulnerability affects krb5/kerberos/negotiate/GSSAPI transfers and could potentially result in unauthorized access to sensitive information. The safest option is to not reuse connections if the CURLOPT_GSSAPI_DELEGATION option has been changed.
A flaw was found in the Curl package. Libcurl keeps previously used connections in a connection pool for subsequent transfers to reuse if one of them matches the setup. However, the GSS delegation setting was left out from the configuration match checks, making them match too easily, affecting krb5/kerberos/negotiate/GSSAPI transfers.

Solutions

amazon-linux-2023-upgrade-curlamazon-linux-2023-upgrade-curl-debuginfoamazon-linux-2023-upgrade-curl-debugsourceamazon-linux-2023-upgrade-curl-minimalamazon-linux-2023-upgrade-curl-minimal-debuginfoamazon-linux-2023-upgrade-libcurlamazon-linux-2023-upgrade-libcurl-debuginfoamazon-linux-2023-upgrade-libcurl-develamazon-linux-2023-upgrade-libcurl-minimalamazon-linux-2023-upgrade-libcurl-minimal-debuginfo
Title
Rapid7 Labs

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