CVE-2018-15910 in Ghostscript
Summary
by MITRE
In Artifex Ghostscript 9.23 before 2018-08-23, attackers able to supply crafted PostScript files could use a type confusion in the LockDistillerParams parameter to crash the interpreter or execute code.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 05/04/2023
The vulnerability CVE-2018-15910 represents a critical type confusion flaw in Artifex Ghostscript version 9.23 that existed prior to the 2018-08-23 security patch release. This issue specifically affects the LockDistillerParams parameter handling within the PostScript interpreter, creating a dangerous condition where improper type handling can lead to arbitrary code execution or denial of service. The vulnerability stems from insufficient input validation and type checking mechanisms that fail to properly distinguish between different data types when processing crafted PostScript files. Attackers can exploit this weakness by crafting malicious PostScript documents that manipulate the LockDistillerParams parameter in ways that cause the interpreter to misinterpret memory contents, leading to unpredictable behavior and potential system compromise.
The technical implementation of this vulnerability involves a classic type confusion attack pattern where the Ghostscript interpreter incorrectly handles parameter types during the distillation process. When a malicious PostScript file is processed, the LockDistillerParams parameter can be manipulated to trigger a scenario where the interpreter attempts to use memory locations as different data types than originally intended. This type confusion allows attackers to manipulate the execution flow of the interpreter, potentially leading to stack corruption or heap-based memory corruption. The vulnerability is particularly dangerous because it can be triggered through legitimate document processing operations, making it difficult to distinguish between benign and malicious input at runtime. According to CWE classification, this maps to CWE-129, which describes improper validation of critical constraints, and CWE-121, which covers stack-based buffer overflow conditions.
The operational impact of CVE-2018-15910 extends beyond simple denial of service scenarios to encompass full system compromise in many environments. When successfully exploited, the vulnerability can enable attackers to execute arbitrary code with the privileges of the Ghostscript process, which typically runs with elevated permissions in many document processing workflows. This makes the vulnerability particularly attractive to threat actors targeting enterprise environments where Ghostscript is used for document conversion, PDF generation, or secure printing operations. The attack surface is broad since Ghostscript is widely deployed across various platforms and applications, including web servers, document management systems, and security appliances that process untrusted PostScript content. The vulnerability can be exploited through multiple vectors including email attachments, web uploads, and file processing workflows that utilize Ghostscript as a backend component, creating numerous potential entry points for attackers.
Mitigation strategies for CVE-2018-15910 should prioritize immediate patching of all affected Ghostscript installations to version 9.23 or later, which contains the necessary fixes for the type confusion vulnerability. Organizations should implement comprehensive input validation and sanitization measures for all PostScript and PDF processing workflows, particularly when handling untrusted content from external sources. Network segmentation and access controls should be strengthened to limit the potential impact of successful exploitation, while monitoring systems should be configured to detect unusual processing patterns or attempted exploitation attempts. Security teams should also consider implementing sandboxing mechanisms for document processing operations and establishing strict file format validation procedures to prevent malicious content from reaching the Ghostscript interpreter. According to ATT&CK framework, this vulnerability aligns with techniques such as T1059.007 for PostScript execution and T1203 for exploitation of software vulnerabilities, making it essential for organizations to maintain up-to-date threat intelligence and incident response capabilities to address potential exploitation attempts.