1. Ubuntu Security Notices
  2. USN-4246-1

USN-4246-1: zlib vulnerabilities

Publication date

22 January 2020

Overview

Several security issues were fixed in zlib

Releases

Packages

  • zlib - Lossless data-compression library

Details

It was discovered that zlib incorrectly handled pointer arithmetic. An attacker
could use this issue to cause zlib to crash, resulting in a denial of
service, or possibly execute arbitrary code. (CVE-2016-9840, CVE-2016-9841)

It was discovered that zlib incorrectly handled vectors involving left shifts of
negative integers. An attacker could use this issue to cause zlib to
crash, resulting in a denial of service, or possibly execute arbitrary code.
(CVE-2016-9842)

It was discovered that zlib incorrectly handled vectors involving big-endian CRC
calculation. An attacker could use this issue to cause zlib to crash,
resulting in a denial of service, or possibly execute arbitrary code.
(CVE-2016-9843)

It was discovered that zlib incorrectly handled pointer arithmetic. An attacker
could use this issue to cause zlib to crash, resulting in a denial of
service, or possibly execute arbitrary code. (CVE-2016-9840, CVE-2016-9841)

It was discovered that zlib incorrectly handled vectors involving left shifts of
negative integers. An attacker could use this issue to cause zlib to
crash, resulting in a denial of service, or possibly execute arbitrary code.
(CVE-2016-9842)

It was discovered that zlib incorrectly handled vectors involving big-endian CRC
calculation. An attacker could use this issue to cause zlib to crash,
resulting in a denial of service, or possibly execute arbitrary code.
(CVE-2016-9843)

Update instructions

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

Learn more about how to get the fixes.

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

Ubuntu Release Package Version
16.04 xenial lib32z1 –  1:1.2.8.dfsg-2ubuntu4.3
lib64z1 –  1:1.2.8.dfsg-2ubuntu4.3
libx32z1 –  1:1.2.8.dfsg-2ubuntu4.3
zlib1g –  1:1.2.8.dfsg-2ubuntu4.3

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References

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