CVE-2021-45949

The PS Interpreter in Ghostscript versions 9.18 and 9.20 allows remote attackers to execute arbitrary code via crafted userparams.

The .sethalftone5 function in Ghostscript before version 9.21 allows remote attackers to cause application crashes or potentially execute arbitrary code via a crafted Postscript document that calls .sethalftone5 with an empty operand stack.

The fill_threshhold_buffer function in base/gxht_thresh.c in Ghostscript 9.20 by Artifex Software, Inc. allows remote attackers to cause a denial of service (heap-based buffer overflow and application crash) or possibly have unspecified other impact via a crafted PostScript document.

Multiple use-after-free vulnerabilities in the gx_image_enum_begin function in base/gxipixel.c in Ghostscript before ecceafe3abba2714ef9b432035fe0739d9b1a283 allow remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact via a crafted PostScript document.

Ghostscript before 10.08.0 contains a heap-based buffer overflow in the JPEG 2000 output adapter (base/sjpx_openjpeg.c). An attacker can cause memory corruption by supplying a crafted PDF containing a JPEG 2000 image with mismatched component subsampling factors. The issue is fixed in version 10.08.0.

Ghostscript before 9.21 might allow remote attackers to bypass the SAFER mode protection mechanism and consequently execute arbitrary code by leveraging type confusion in .initialize_dsc_parser.

A use-after-free vulnerability in Ghostscript 9.20 may allow remote attackers to execute arbitrary code via reference leaks in the .setdevice function.

A flaw in Ghostscript allows bypassing the -dSAFER sandbox and executing arbitrary shell commands in the context of the Ghostscript process when rendering a crafted PostScript or EPS document. The issue chains memory corruption in document parsing with disabling of internal path access controls at runtime.

Ghostscript for Windows is vulnerable to local privilege escalation through PostScript resource file hijacking. The application searches for resource files in predictable paths under C:\gs\ that do not exist by default, and Windows default ACLs allow any authenticated user to create directories at the root of C:\. An attacker can create the expected directory structure and plant a malicious PostScript file, which is executed with full privileges of the Ghostscript process. Fixed in version 10.08.0.

A flaw was found in ghostscript for Red Hat Enterprise Linux 8, where the fix for CVE-2020-16305 was not included as previously claimed. This issue affects the ghostscript package specifically.