USN-4246-1: zlib vulnerabilities

Releases

• Ubuntu 16.04 ESM

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)

Update instructions

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

Ubuntu 16.04

• 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

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

References

• CVE-2016-9840
• CVE-2016-9841
• CVE-2016-9842
• CVE-2016-9843

Related notices

• USN-4292-1: rsync
• USN-6736-1: libklibc, libklibc-dev, klibc, klibc-utils