ALAS2-2021-1598 --- ghostscript, libgsID: oval:org.secpod.oval:def:1700556 | Date: (C)2021-02-22 (M)2024-04-17 |
Class: PATCH | Family: unix |
Artifex Ghostscript before 9.25 allowed a user-writable error exception table, which could be used by remote attackers able to supply crafted PostScript to potentially overwrite or replace error handlers to inject code. Artifex Ghostscript 9.25 and earlier allows attackers to bypass a sandbox protection mechanism via vectors involving errorhandler setup. NOTE: this issue exists because of an incomplete fix for CVE-2018-17183 . Artifex Ghostscript allows attackers to bypass a sandbox protection mechanism by leveraging exposure of system operators in the saved execution stack in an error object. Artifex Ghostscript 9.25 and earlier allows attackers to bypass a sandbox protection mechanism via vectors involving the 1Policy operator. In Artifex Ghostscript through 9.25, the setpattern operator did not properly validate certain types. A specially crafted PostScript document could exploit this to crash Ghostscript or, possibly, execute arbitrary code in the context of the Ghostscript process. This is a type confusion issue because of failure to check whether the Implementation of a pattern dictionary was a structure type. An issue was discovered in Artifex Ghostscript before 9.26. LockSafetyParams is not checked correctly if another device is used. psi/zdevice2.c in Artifex Ghostscript before 9.26 allows remote attackers to bypass intended access restrictions because available stack space is not checked when the device remains the same. psi/zicc.c in Artifex Ghostscript before 9.26 allows remote attackers to bypass intended access restrictions because of a setcolorspace type confusion. psi/zfjbig2.c in Artifex Ghostscript before 9.26 allows remote attackers to bypass intended access restrictions because of a JBIG2Decode type confusion. A flaw was found in the .pdf_hook_DSC_Creator procedure where it did not properly secure its privileged calls, enabling scripts to bypass `-dSAFER` restrictions. A specially crafted PostScript file could disable security protection and then have access to the file system, or execute arbitrary commands. A flaw was found in the .setuserparams2 procedure where it did not properly secure its privileged calls, enabling scripts to bypass `-dSAFER` restrictions. A specially crafted PostScript file could disable security protection and then have access to the file system, or execute arbitrary commands. A flaw was found in the setsystemparams procedure where it did not properly secure its privileged calls, enabling scripts to bypass `-dSAFER` restrictions. A specially crafted PostScript file could disable security protection and then have access to the file system, or execute arbitrary commands. A flaw was found in the .pdfexectoken and other procedures where it did not properly secure its privileged calls, enabling scripts to bypass `-dSAFER` restrictions. A specially crafted PostScript file could disable security protection and then have access to the file system, or execute arbitrary commands. A flaw was found in the `.charkeys` procedure, where it did not properly secure its privileged calls, enabling scripts to bypass `-dSAFER` restrictions. An attacker could abuse this flaw by creating a specially crafted PostScript file that could escalate privileges within the Ghostscript and access files outside of restricted areas or execute commands. It was found that the superexec operator was available in the internal dictionary. A specially crafted PostScript file could use this flaw in order to, for example, have access to the file system outside of the constrains imposed by -dSAFER. It was found that the forceput operator could be extracted from the DefineResource method. A specially crafted PostScript file could use this flaw in order to, for example, have access to the file system outside of the constrains imposed by -dSAFER. It was found that some privileged operators remained accessible from various places after the CVE-2019-6116 fix. A specially crafted PostScript file could use this flaw in order to, for example, have access to the file system outside of the constrains imposed by -dSAFER. It was found that ghostscript could leak sensitive operators on the operand stack when a pseudo-operator pushes a subroutine. A specially crafted PostScript file could use this flaw to escape the -dSAFER protection in order to, for example, have access to the file system outside of the SAFER constraints