CVE-2020-36773

Publication date 4 February 2024

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

Artifex Ghostscript before 9.53.0 has an out-of-bounds write and use-after-free in devices/vector/gdevtxtw.c (for txtwrite) because a single character code in a PDF document can map to more than one Unicode code point (e.g., for a ligature).

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
ghostscript	24.04 LTS noble	Not affected
	23.10 mantic	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Ignored end of standard support

Notes

mdeslaur

This issue was introduced in 9.51 as described in the patch. The reproducer doesn't work on focal.

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
ghostscript	Upstream: https://git.ghostscript.com/?p=ghostpdl.git;h=8c7bd787defa071c96289b7da9397f673fddb874

Severity score breakdown

Parameter	Value
Base score	9.8 · Critical
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	High
Integrity impact	High
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H