CVE-2023-4042 is a medium severity vulnerability identified in the ghostscript package as distributed with Red Hat Enterprise Linux 8. The issue is an out-of-bounds read, which occurs when the software reads memory outside the intended buffer boundaries. This flaw was originally addressed in CVE-2020-16305, but the fix was not included in the RHSA-2021:1852-06 advisory as previously claimed, leaving the vulnerability unpatched in Red Hat's distribution. Ghostscript is a widely used interpreter for PostScript and PDF files, often employed in printing and document processing workflows. The vulnerability requires local access (AV:L) and low attack complexity (AC:L), with no privileges required (PR:N), but does require user interaction (UI:R). The impact is limited to availability (A:H), meaning the vulnerability can cause application crashes or denial of service but does not compromise confidentiality or integrity. No known exploits have been reported in the wild, but the presence of this flaw could allow attackers with local access to disrupt services relying on ghostscript. The vulnerability affects only the ghostscript package as shipped with Red Hat Enterprise Linux 8, and no other versions or distributions are indicated as impacted. The CVSS vector indicates the scope remains unchanged (S:U), confirming the impact is contained to the vulnerable component without escalation to other system components.

For European organizations, the primary impact of CVE-2023-4042 is potential denial of service in systems utilizing ghostscript on Red Hat Enterprise Linux 8. This could disrupt printing services, document processing pipelines, or any automated workflows relying on ghostscript, potentially affecting business continuity. While the vulnerability does not expose sensitive data or allow privilege escalation, the availability impact can be significant in environments where ghostscript is integrated into critical infrastructure or production systems. Organizations in sectors such as government, finance, healthcare, and manufacturing that rely on Red Hat Enterprise Linux 8 for their server infrastructure may experience operational disruptions if exploited. The requirement for local access and user interaction limits remote exploitation risk, but insider threats or compromised user accounts could leverage this vulnerability to cause service interruptions. The absence of known exploits reduces immediate risk but does not eliminate the need for timely remediation to prevent future attacks.

European organizations should monitor Red Hat security advisories closely for the release of an official patch addressing CVE-2023-4042. Until a patch is available, mitigating controls include restricting local user access to systems running Red Hat Enterprise Linux 8 with ghostscript installed, enforcing strict user privilege management, and monitoring for unusual application crashes or service disruptions related to ghostscript. Implement application whitelisting and endpoint detection to identify potential exploitation attempts. Additionally, organizations should review and harden document processing workflows to minimize reliance on ghostscript where feasible or isolate ghostscript usage within sandboxed environments to contain potential crashes. Regularly audit installed package versions and ensure that ghostscript is updated promptly once the fix is released. Employing comprehensive logging and alerting for local user activities can help detect attempts to trigger the vulnerability.