CVE-2022-32208 is a medium-severity vulnerability affecting curl versions prior to 7.84.0, specifically in the handling of FTP transfers secured by Kerberos 5 (krb5). Curl is a widely used command-line tool and library for transferring data with URLs, supporting numerous protocols including FTP. The vulnerability arises from improper handling of message verification failures during krb5-secured FTP transfers. When such verification fails, curl does not correctly detect or respond to the failure, allowing a Man-In-The-Middle (MITM) attacker to remain undetected. Furthermore, the attacker can inject arbitrary data into the client’s data stream. This represents a business logic error categorized under CWE-840, where the application logic incorrectly handles error conditions, leading to security bypass. The CVSS 3.1 base score is 5.9, indicating a medium severity, with the vector AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N. This means the attack can be performed remotely over the network without privileges or user interaction, but requires high attack complexity. The impact is primarily on confidentiality, as the attacker can intercept and inject data without detection, but integrity and availability are not directly affected. No known exploits in the wild have been reported to date. The vulnerability was fixed in curl version 7.84.0, and users are advised to upgrade to this or later versions to mitigate the risk.

For European organizations, this vulnerability poses a risk primarily to systems and applications that utilize curl for FTP transfers secured by krb5 authentication. Such scenarios are common in enterprise environments where secure file transfers are automated or integrated into workflows, especially in sectors like finance, government, and critical infrastructure that rely on Kerberos for authentication. The ability for an attacker to perform a MITM attack undetected and inject data could lead to unauthorized data disclosure, data manipulation at the transport layer, or insertion of malicious payloads, potentially compromising sensitive information or disrupting business processes. Although the attack complexity is high, the lack of required privileges or user interaction means that exposed systems accessible over the network are at risk. European organizations with legacy systems or those slow to update curl may be particularly vulnerable. Additionally, given the widespread use of curl in various software stacks, indirect exposure through third-party applications is possible. The confidentiality breach could have regulatory implications under GDPR if personal or sensitive data is intercepted or altered.

To mitigate this vulnerability, European organizations should: 1) Immediately audit all systems and applications using curl for FTP transfers with krb5 authentication and identify versions prior to 7.84.0. 2) Upgrade curl to version 7.84.0 or later, where the vulnerability is patched. 3) For environments where immediate upgrade is not feasible, consider disabling FTP over krb5 or restricting such transfers to trusted internal networks only. 4) Implement network-level protections such as TLS/SSL tunneling or VPNs to add an additional layer of encryption and integrity verification beyond krb5 FTP. 5) Monitor network traffic for unusual patterns indicative of MITM attacks, including unexpected data injections or anomalies in FTP sessions. 6) Review and enhance logging and alerting mechanisms around FTP transfers to detect potential exploitation attempts. 7) Engage with software vendors and third-party providers to ensure their curl dependencies are updated accordingly. These steps go beyond generic patching by emphasizing network controls, monitoring, and operational awareness tailored to the specific nature of this vulnerability.