CVE-2016-9840: High severity Apple tvOS vulnerability

Published Dec 7, 2016
·
Updated

inftrees.c in zlib 1.2.8 might allow context-dependent attackers to have unspecified impact by leveraging improper pointer arithmetic

Other sources

inftrees.c was subtracting an offset from a pointer to an array, in order to provide a pointer that allowed indexing starting at the offset. This is not compliant with the C standard, for which the behavior of a pointer decremented before its allocated memory is undefined.

External References:

https://wiki.mozilla.org/images/0/09/Zlib-report.pdf https://docs.google.com/document/d/10i1KZS5so8xDqH2rplRa2xet0tyTvvJlLbQQmZIUIKE/edit#heading=h.t13tvnx4loq7

Upstream patch:

https://github.com/madler/zlib/commit/6a043145ca6e9c55184013841a67b2fef87e44c0

CVE assignment:

http://seclists.org/oss-sec/2016/q4/602

Red Hat

zlib. Multiple issues were addressed by updating to version 1.2.11.

Credit

CVE-2016-9840, CVE-2016-9841, CVE-2016-9842, CVE-2016-9843, CVE-2016-9840, CVE-2016-9841, CVE-2016-9842, CVE-2016-9843

Affected Software

51 affected componentsFixes available
Apple tvOS<11
11
Apple macOS High Sierra<10.13
10.13
Apple WatchOS<4
4
Apple iOS<11
11
boost boost<1.78.0
zlib zlib>=1.2.0.6<1.2.9
openSUSE Leap=42.1
openSUSE Leap=42.2
openSUSE openSUSE=13.2
Debian Debian Linux=8.0
Canonical Ubuntu Linux=16.04
Canonical Ubuntu Linux=18.04
Oracle Database Server=18c
Oracle JDK=1.6.0-update161
Oracle JDK=1.7.0-update151
Oracle JDK=1.8.0-update144
Oracle JRE=1.6.0-update161
Oracle JRE=1.7.0-update151
Oracle JRE=1.8.0-update144
Oracle MySQL>=5.5.0<=5.5.61
Oracle MySQL>=5.6.0<=5.6.41
Oracle MySQL>=5.7.0<=5.7.23
Oracle MySQL>=8.0.0<=8.0.12
redhat Satellite=5.8
redhat Enterprise Linux Desktop=6.0
redhat Enterprise Linux Desktop=7.0
redhat Enterprise Linux Eus=7.4
redhat Enterprise Linux Eus=7.5
redhat Enterprise Linux Server=6.0
redhat Enterprise Linux Server=7.0
redhat Enterprise Linux Workstation=6.0
redhat Enterprise Linux Workstation=7.0
Apple iPhone OS<11
Apple iOS and macOS>=10.0.0<10.13.0
Apple tvOS<11.0
Apple WatchOS<4
Nodejs Node.js>=4.0.0<=4.1.2
Nodejs Node.js>=4.2.0<4.8.2
Nodejs Node.js>=6.0.0<=6.8.1
Nodejs Node.js>=6.9.0<6.10.2
Nodejs Node.js>=7.0.0<7.6.0
Canonical Ubuntu Linux=18.04
redhat/zlib<1.2.9
1.2.9
F5 BIG-IP=17.5.0, >=17.1.0<=17.1.2
17.5.117.1.3
F5 BIG-IP>=16.1.0<=16.1.6
F5 BIG-IP>=15.1.0<=15.1.10
F5 BIG-IQ Centralized Management>=8.2.0<=8.4.0
Microsoft azl3 fltk 1.3.8-1
Microsoft cbl2 boost 1.76.0-4
debian/rsync
3.2.3-4+deb11u13.2.3-4+deb11u33.2.7-1+deb12u43.2.7-1+deb12u23.4.1+ds1-5+deb13u13.4.1+ds1-7
debian/zlib
1:1.2.11.dfsg-2+deb11u21:1.2.13.dfsg-11:1.3.dfsg+really1.3.1-11:1.3.dfsg+really1.3.1-3

Event History

Dec 7, 2016
Data Sourced
via Red Hat·10:03 AM
DescriptionSeverityAffected Software
May 23, 2017
CVE Published
via MITRE·03:56 AM
Data Sourced
via MITRE·03:56 AM
Description
Jan 11, 2024
Data Sourced
via Launchpad·10:23 PM
Description
Feb 20, 2025
Advisory Published
via F5·11:35 PM
Data Sourced
via F5·11:35 PM
DescriptionSeverityWeaknessAffected Software
Mar 14, 2025
Data Sourced
via Microsoft·07:00 AM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·07:00 AM
Affected Software
Updated
via Microsoft·07:00 AM
DescriptionSeverity
Dec 24, 2025
Data Sourced
via Ubuntu·05:09 PM
RemedyDescriptionSeverityAffected Software
Feb 19, 2026
Data Sourced
via Debian·07:18 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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Frequently Asked Questions

1

What is the severity of CVE-2016-9840?

CVE-2016-9840 has been classified with a severity that could allow attackers to exploit improper pointer arithmetic leading to unspecified impact.

2

How do I fix CVE-2016-9840?

To fix CVE-2016-9840, update zlib to version 1.2.9 or later, or apply vendor-specific patches as applicable.

3

Which software versions are affected by CVE-2016-9840?

CVE-2016-9840 affects zlib versions prior to 1.2.9 and several operating systems including older versions of iOS, macOS, and various Linux distributions.

4

Can CVE-2016-9840 be exploited remotely?

CVE-2016-9840 may allow context-dependent attackers to exploit applications using the vulnerable zlib library, potentially leading to remote attacks.

5

What are the consequences of CVE-2016-9840 exploitation?

Exploitation of CVE-2016-9840 could result in application crashes or arbitrary code execution due to improper handling of pointers.

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