CVE-2023-4042 is a medium severity vulnerability affecting the ghostscript package included in Red Hat Enterprise Linux 8. The issue arises because a fix for a previous vulnerability, CVE-2020-16305, was not incorporated in the RHSA-2021:1852-06 advisory as intended. This results in an out-of-bounds read condition within ghostscript, which can cause the application to crash, leading to a denial of service (DoS) condition. The vulnerability does not allow for unauthorized data disclosure or modification, as indicated by the CVSS vector (Confidentiality: None, Integrity: None, Availability: High). The attack vector is local (AV:L), requiring the attacker to have local access to the system. The attack complexity is low (AC:L), and no privileges are required (PR:N), but user interaction is necessary (UI:R), meaning the attacker must convince a user to trigger the vulnerability. The scope remains unchanged (S:U), affecting only the vulnerable component. Currently, there are no known exploits in the wild, and no patches have been explicitly linked in the provided data, though Red Hat is expected to release updates. The vulnerability primarily impacts systems running RHEL 8 with ghostscript installed, which is commonly used for processing PostScript and PDF files in various enterprise environments.

For European organizations, the primary impact of CVE-2023-4042 is the potential for denial of service on systems running Red Hat Enterprise Linux 8 with the vulnerable ghostscript package. This could disrupt services that rely on document processing or printing workflows, potentially affecting business continuity. While the vulnerability does not compromise data confidentiality or integrity, the availability impact could be significant in environments where uptime is critical, such as financial institutions, government agencies, and critical infrastructure operators. Organizations with automated document processing pipelines or print servers using ghostscript may experience service interruptions if exploited. The requirement for local access and user interaction limits the attack surface but does not eliminate risk, especially in environments with multiple users or where attackers may have gained initial footholds. The absence of known exploits reduces immediate risk but does not preclude future exploitation attempts.

European organizations should proactively monitor Red Hat security advisories for patches addressing CVE-2023-4042 and apply them promptly once available. Until patches are deployed, restrict local access to systems running RHEL 8 with ghostscript to trusted users only. Implement strict user privilege management to minimize the number of users who can execute or interact with ghostscript processes. Employ application whitelisting and endpoint detection to identify and block suspicious attempts to trigger ghostscript. Consider isolating document processing services in sandboxed or containerized environments to limit the impact of potential crashes. Regularly audit and monitor logs for unusual activity related to ghostscript usage. Educate users about the risks of interacting with untrusted files or prompts that could trigger the vulnerability. Finally, maintain up-to-date backups and incident response plans to quickly recover from any denial of service incidents.