[USN-4111-1] Ghostscript vulnerabilities

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Ubuntu Security Notice USN-4111-1
August 29, 2019

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

- Ubuntu 19.04
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

Ghostscript could be made to access arbitrary files if it opened a
specially crafted file.

Software Description:
- ghostscript: PostScript and PDF interpreter

Details:

Hiroki Matsukuma discovered that the PDF interpreter in Ghostscript
did not properly restrict privileged calls when '-dSAFER'
restrictions were in effect. If a user or automated system were
tricked into processing a specially crafted file, a remote attacker
could possibly use this issue to access arbitrary files.
(CVE-2019-14811, CVE-2019-14812, CVE-2019-14813, CVE-2019-14817)

Update instructions:

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

Ubuntu 19.04:
ghostscript 9.26~dfsg+0-0ubuntu7.3
libgs9 9.26~dfsg+0-0ubuntu7.3

Ubuntu 18.04 LTS:
ghostscript 9.26~dfsg+0-0ubuntu0.18.04.11
libgs9 9.26~dfsg+0-0ubuntu0.18.04.11

Ubuntu 16.04 LTS:
ghostscript 9.26~dfsg+0-0ubuntu0.16.04.11
libgs9 9.26~dfsg+0-0ubuntu0.16.04.11

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

References:
https://usn.ubuntu.com/4111-1
CVE-2019-14811, CVE-2019-14812, CVE-2019-14813, CVE-2019-14817

Package Information:
https://launchpad.net/ubuntu/+source/ghostscript/9.26~dfsg+0-0ubuntu7.3
https://launchpad.net/ubuntu/+source/ghostscript/9.26~dfsg+0-0ubuntu0.18.04.11
https://launchpad.net/ubuntu/+source/ghostscript/9.26~dfsg+0-0ubuntu0.16.04.11