--- title: "CVE-2016-9840\n | Ubuntu" description: Ubuntu is an open source software operating system that runs from the desktop, to the cloud, to all your internet connected things. url: https://ubuntu.com/security/CVE-2016-9840?format=md keywords: index, follow --- # CVE-2016-9840 Publication date 23 May 2017 Last updated 11 July 2025 --- Ubuntu priority **Low** [Why this priority?](https://ubuntu.com/security/cves/about#priority ) ## Cvss 3 Severity Score **8.8 · High** [Score breakdown](https://ubuntu.com/security/CVE-2016-9840?format=md#impact-score) Toggle side navigation ## Description inftrees.c in zlib 1.2.8 might allow context-dependent attackers to have unspecified impact by leveraging improper pointer arithmetic. [Read the notes from the security team](https://ubuntu.com/security/CVE-2016-9840?format=md#notes) ## Status Show unmaintained releases | Package | Ubuntu Release | Status | | --- | --- | --- | | zsync | 26.04 LTS resolute | Needs evaluation | | 25.10 questing | Ignored end of life, was needs-triage | | 25.04 plucky | Ignored end of life, was needs-triage | | 24.10 oracular | Ignored end of life, was needs-triage | | 24.04 LTS noble | Needs evaluation | | 22.04 LTS jammy | Needs evaluation | | 20.04 LTS focal | Needs evaluation | | 18.04 LTS bionic | Needs evaluation | | 16.04 LTS xenial | Needs evaluation | | klibc | 26.04 LTS resolute | Fixed 2.0.13-4ubuntu1 | | 25.10 questing | Fixed 2.0.13-4ubuntu1 | | 25.04 plucky | Fixed 2.0.13-4ubuntu1 | | 24.10 oracular | Fixed 2.0.13-4ubuntu1 | | 24.04 LTS noble | Fixed 2.0.13-4ubuntu0.1 | | 23.10 mantic | Fixed 2.0.13-1ubuntu0.1 | | 22.04 LTS jammy | Fixed 2.0.10-4ubuntu0.1 | | 20.04 LTS focal | Fixed 2.0.7-1ubuntu5.2 | | 18.04 LTS bionic | Fixed 2.0.4-9ubuntu2.2+esm1 Ubuntu Pro | | 16.04 LTS xenial | Fixed 2.0.4-8ubuntu1.16.04.4+esm2 Ubuntu Pro | | 14.04 LTS trusty | Fixed 2.0.3-0ubuntu1.14.04.3+esm3 Ubuntu Pro | | rsync | 26.04 LTS resolute | Fixed 3.1.3-6 | | 25.10 questing | Fixed 3.1.3-6 | | 25.04 plucky | Fixed 3.1.3-6 | | 24.10 oracular | Fixed 3.1.3-6 | | 24.04 LTS noble | Fixed 3.1.3-6 | | 23.10 mantic | Fixed 3.1.3-6 | | 23.04 lunar | Fixed 3.1.3-6 | | 22.10 kinetic | Fixed 3.1.3-6 | | 22.04 LTS jammy | Fixed 3.1.3-6 | | 21.10 impish | Fixed 3.1.3-6 | | 21.04 hirsute | Fixed 3.1.3-6 | | 20.10 groovy | Fixed 3.1.3-6 | | 20.04 LTS focal | Fixed 3.1.3-6 | | 19.10 eoan | Fixed 3.1.3-6 | | 19.04 disco | Fixed 3.1.3-6 | | 18.04 LTS bionic | Fixed 3.1.2-2.1ubuntu1.1 | | 16.04 LTS xenial | Fixed 3.1.1-3ubuntu1.3 | | 14.04 LTS trusty | Not affected | | zlib | 26.04 LTS resolute | Not affected | | 25.10 questing | Not affected | | 25.04 plucky | Not affected | | 24.10 oracular | Not affected | | 24.04 LTS noble | Not affected | | 23.10 mantic | Not affected | | 23.04 lunar | Not affected | | 22.10 kinetic | Not affected | | 22.04 LTS jammy | Not affected | | 21.10 impish | Not affected | | 21.04 hirsute | Not affected | | 20.10 groovy | Not affected | | 20.04 LTS focal | Not affected | | 19.10 eoan | Not affected | | 19.04 disco | Not affected | | 18.10 cosmic | Not affected | | 18.04 LTS bionic | Not affected | | 17.10 artful | Not affected | | 17.04 zesty | Ignored end of life | | 16.10 yakkety | Ignored end of life | | 16.04 LTS xenial | Fixed 1:1.2.8.dfsg-2ubuntu4.3 | | 14.04 LTS trusty | Vulnerable | | 12.04 LTS precise | Ignored end of life | --- * [How can I get the fixes?](https://ubuntu.com/security/cves/about#security) * [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses) * [Patch details](https://ubuntu.com/security/CVE-2016-9840?format=md#patch-details) ### Get expanded security coverage with Ubuntu Pro Reduce your average CVE exposure time from 98 days to 1 day with expanded CVE patching, ten-years security maintenance and optional support for the full stack of open-source applications. Free for personal use. [Get Ubuntu Pro](https://ubuntu.com/pro) [30-day free trial](https://ubuntu.com/pro/free-trial) ## Notes --- ### [mdeslaur](https://launchpad.net/~mdeslaur) since 3.1.3-7, rsync builds with the system zlib ### Patch details For informational purposes only. We recommend not to cherry-pick updates. [How can I get the fixes?](https://ubuntu.com/security/cves/about#security) | Package | Patch details | | --- | --- | | zlib | * Upstream: [6a04314](https://github.com/madler/zlib/commit/6a043145ca6e9c55184013841a67b2fef87e44c0) | ## Severity score breakdown CVSS version: CVSS v3.0 **Base score** 8.8 · High * Base metrics | Parameter | Value | | --- | --- | | Attack vector | Network | | Attack complexity | Low | | Privileges required | None | | User interaction | Required | | Scope | Unchanged | | Confidentiality impact | High | | Integrity impact | High | | Availability impact | High | * Scores | Parameter | Value | | --- | --- | | Base score | 8.8 · High | | Exploitability score | - | | Impact score | - | **Vector:** CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H ## References * [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-9840) * [NVD](https://nvd.nist.gov/vuln/detail/CVE-2016-9840) * [Launchpad](https://launchpad.net/bugs/cve/CVE-2016-9840) * [Debian](https://security-tracker.debian.org/tracker/CVE-2016-9840) ### Related Ubuntu Security Notices (USN) + [USN-4246-1](https://usn.ubuntu.com/USN-4246-1) + zlib vulnerabilities + 22 January 2020 + [USN-4292-1](https://usn.ubuntu.com/USN-4292-1) + rsync vulnerabilities + 25 February 2020 + [USN-6736-1](https://usn.ubuntu.com/USN-6736-1) + klibc vulnerabilities + 16 April 2024 + [USN-6736-2](https://usn.ubuntu.com/USN-6736-2) + klibc vulnerabilities + 23 May 2024 ### Other references * *