This vulnerability in HotelRunner B2B arises from improper validation of TLS/SSL certificates when the hostname does not match the certificate. This flaw allows an attacker to perform HTTP Response Splitting, potentially manipulating HTTP responses. The affected versions are before 04.06.2025. The CVSS 3.1 base score is 4.6, reflecting a medium severity with network attack vector, low attack complexity, requiring low privileges and user interaction, and impacts confidentiality and integrity with no availability impact.

Successful exploitation could allow an attacker to manipulate HTTP responses via response splitting, potentially leading to information disclosure or integrity issues. However, the impact is limited to confidentiality and integrity with no direct availability impact. No known exploits have been reported in the wild.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no patch or official fix is currently indicated, monitor for vendor updates and apply any official patches once available. In the meantime, consider mitigating controls specific to HTTP response handling if applicable.