--- title: "CVE-2019-1547\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-2019-1547?format=md keywords: index, follow --- # CVE-2019-1547 Publication date 10 September 2019 Last updated 25 August 2025 --- Ubuntu priority **Low** [Why this priority?](https://ubuntu.com/security/cves/about#priority ) ## Cvss 3 Severity Score **4.7 · Medium** [Score breakdown](https://ubuntu.com/security/CVE-2019-1547?format=md#impact-score) Toggle side navigation ## Description Normally in OpenSSL EC groups always have a co-factor present and this is used in side channel resistant code paths. However, in some cases, it is possible to construct a group using explicit parameters (instead of using a named curve). In those cases it is possible that such a group does not have the cofactor present. This can occur even where all the parameters match a known named curve. If such a curve is used then OpenSSL falls back to non-side channel resistant code paths which may result in full key recovery during an ECDSA signature operation. In order to be vulnerable an attacker would have to have the ability to time the creation of a large number of signatures where explicit parameters with no co-factor present are in use by an application using libcrypto. For the avoidance of doubt libssl is not vulnerable because explicit parameters are never used. Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c). Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k). Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s). [Read the notes from the security team](https://ubuntu.com/security/CVE-2019-1547?format=md#notes) ## Status Show unmaintained releases | Package | Ubuntu Release | Status | | --- | --- | --- | | edk2 | 20.04 LTS focal | Not affected | | 19.10 eoan | Not affected | | 19.04 disco | Not affected | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Not affected | | 14.04 LTS trusty | Not in release | | nodejs | 20.04 LTS focal | Not affected | | 19.10 eoan | Not affected | | 19.04 disco | Not affected | | 18.04 LTS bionic | Not affected | | 16.04 LTS xenial | Not affected | | 14.04 LTS trusty | Not affected | | openssl | 20.04 LTS focal | Fixed 1.1.1d-2ubuntu1 | | 19.10 eoan | Fixed 1.1.1c-1ubuntu4.1 | | 19.04 disco | Ignored end of life | | 18.04 LTS bionic | Fixed 1.1.1-1ubuntu2.1~18.04.6 | | 16.04 LTS xenial | Fixed 1.0.2g-1ubuntu4.16 | | 14.04 LTS trusty | Fixed 1.0.1f-1ubuntu2.27+esm1 Ubuntu Pro | | openssl1.0 | 20.04 LTS focal | Not in release | | 19.10 eoan | Not in release | | 19.04 disco | Not in release | | 18.04 LTS bionic | Fixed 1.0.2n-1ubuntu5.4 | | 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-2019-1547?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) code isn't compiled into edk2 ### 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 | | --- | --- | | openssl | * Upstream: * Upstream: * Upstream: | ## Severity score breakdown CVSS version: CVSS v3.0 **Base score** 4.7 · Medium * Base metrics | Parameter | Value | | --- | --- | | Attack vector | Local | | Attack complexity | High | | Privileges required | Low | | User interaction | None | | Scope | Unchanged | | Confidentiality impact | High | | Integrity impact | None | | Availability impact | None | * Scores | Parameter | Value | | --- | --- | | Base score | 4.7 · Medium | | Exploitability score | - | | Impact score | - | **Vector:** CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N ## References * [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-1547) * [NVD](https://nvd.nist.gov/vuln/detail/CVE-2019-1547) * [Launchpad](https://launchpad.net/bugs/cve/CVE-2019-1547) * [Debian](https://security-tracker.debian.org/tracker/CVE-2019-1547) ### Related Ubuntu Security Notices (USN) + [USN-4376-1](https://usn.ubuntu.com/USN-4376-1) + OpenSSL vulnerabilities + 28 May 2020 + [USN-4376-2](https://usn.ubuntu.com/USN-4376-2) + OpenSSL vulnerabilities + 9 July 2020 + [USN-4504-1](https://usn.ubuntu.com/USN-4504-1) + OpenSSL vulnerabilities + 16 September 2020 ### Other references * *