--- title: "CVE-2018-1000030\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-2018-1000030?format=md keywords: index, follow --- # CVE-2018-1000030 Publication date 8 February 2018 Last updated 25 August 2025 --- Ubuntu priority **Low** [Why this priority?](https://ubuntu.com/security/cves/about#priority ) ## Cvss 3 Severity Score **3.6 · Low** [Score breakdown](https://ubuntu.com/security/CVE-2018-1000030?format=md#impact-score) Toggle side navigation ## Description Python 2.7.14 is vulnerable to a Heap-Buffer-Overflow as well as a Heap-Use-After-Free. Python versions prior to 2.7.14 may also be vulnerable and it appears that Python 2.7.17 and prior may also be vulnerable however this has not been confirmed. The vulnerability lies when multiply threads are handling large amounts of data. In both cases there is essentially a race condition that occurs. For the Heap-Buffer-Overflow, Thread 2 is creating the size for a buffer, but Thread1 is already writing to the buffer without knowing how much to write. So when a large amount of data is being processed, it is very easy to cause memory corruption using a Heap-Buffer-Overflow. As for the Use-After-Free, Thread3->Malloc->Thread1->Free's->Thread2-Re-uses-Free'd Memory. The PSRT has stated that this is not a security vulnerability due to the fact that the attacker must be able to run code, however in some situations, such as function as a service, this vulnerability can potentially be used by an attacker to violate a trust boundary, as such the DWF feels this issue deserves a CVE. [Read the notes from the security team](https://ubuntu.com/security/CVE-2018-1000030?format=md#notes) ## Status Show unmaintained releases | Package | Ubuntu Release | Status | | --- | --- | --- | | python2.6 | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 17.10 artful | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | python2.7 | 18.10 cosmic | Not affected | | 18.04 LTS bionic | Not affected | | 17.10 artful | Ignored end of life | | 16.04 LTS xenial | Fixed 2.7.12-1ubuntu0~16.04.4 | | 14.04 LTS trusty | Fixed 2.7.6-8ubuntu0.5 | | python3.2 | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 17.10 artful | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | python3.4 | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 17.10 artful | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not affected | | python3.5 | 18.10 cosmic | Not in release | | 18.04 LTS bionic | Not in release | | 17.10 artful | Not in release | | 16.04 LTS xenial | Not affected | | 14.04 LTS trusty | Not affected | | python3.6 | 18.10 cosmic | Not affected | | 18.04 LTS bionic | Not affected | | 17.10 artful | Not affected | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | python3.7 | 18.10 cosmic | Not affected | | 18.04 LTS bionic | Not affected | | 17.10 artful | Not affected | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | --- * [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-2018-1000030?format=md#patch-details) ## Notes --- ### [mdeslaur](https://launchpad.net/~mdeslaur) original fix caused a regression, see second commit ### 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 | | --- | --- | | python2.7 | * Upstream: [6401e56](https://github.com/python/cpython/commit/6401e5671781eb217ee1afb4603cc0d1b0367ae6) * Upstream: [dbf52e0](https://github.com/python/cpython/commit/dbf52e02f18dac6f5f0a64f78932f3dc6efc056b) | ## Severity score breakdown CVSS version: CVSS v3.0 **Base score** 3.6 · Low * Base metrics | Parameter | Value | | --- | --- | | Attack vector | Local | | Attack complexity | High | | Privileges required | Low | | User interaction | None | | Scope | Unchanged | | Confidentiality impact | Low | | Integrity impact | None | | Availability impact | Low | * Scores | Parameter | Value | | --- | --- | | Base score | 3.6 · Low | | Exploitability score | - | | Impact score | - | **Vector:** CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:L ## References * [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-1000030) * [NVD](https://nvd.nist.gov/vuln/detail/CVE-2018-1000030) * [Launchpad](https://launchpad.net/bugs/cve/CVE-2018-1000030) * [Debian](https://security-tracker.debian.org/tracker/CVE-2018-1000030) ### Related Ubuntu Security Notices (USN) + [USN-3817-1](https://usn.ubuntu.com/USN-3817-1) + Python vulnerabilities + 13 November 2018 + [USN-3817-2](https://usn.ubuntu.com/USN-3817-2) + Python vulnerabilities + 15 November 2018 ### Other references *