A Ghostscript vulnerabilities security update has been released for Ubuntu 16.04 LTS and 18.04 LTS.

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Ubuntu Security Notice USN-4686-1
January 07, 2021

ghostscript vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

Several security issues were fixed in Ghostscript.

Software Description:
- ghostscript: PostScript and PDF interpreter

Details:

It was discovered that Ghostscript incorrectly handled certain image
files. If a user or automated system were tricked into processing a
specially crafted file, a remote attacker could use this issue to cause
Ghostscript to crash, resulting in a denial of service, or possibly
execute arbitrary code.

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 18.04 LTS:
ghostscript 9.26~dfsg+0-0ubuntu0.18.04.14
libgs9 9.26~dfsg+0-0ubuntu0.18.04.14

Ubuntu 16.04 LTS:
ghostscript 9.26~dfsg+0-0ubuntu0.16.04.14
libgs9 9.26~dfsg+0-0ubuntu0.16.04.14

In general, a standard system update will make all the necessary changes.

References:
  https://usn.ubuntu.com/4686-1
CVE-2018-5727, CVE-2020-27814, CVE-2020-27824, CVE-2020-27841,
CVE-2020-27842, CVE-2020-27843, CVE-2020-27845, CVE-2020-6851,
CVE-2020-8112

Package Information:
  https://launchpad.net/ubuntu/+source/ghostscript/9.26~dfsg+0-0ubuntu0.18.04.14
  https://launchpad.net/ubuntu/+source/ghostscript/9.26~dfsg+0-0ubuntu0.16.04.14