---
title: "CVE-2015-0837\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-2015-0837?format=md
keywords: index, follow
---

# CVE-2015-0837

Publication date 2 March 2015

Last updated 25 August 2025

---

Ubuntu priority

**Low**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**5.9 · Medium**

[Score breakdown](https://ubuntu.com/security/CVE-2015-0837?format=md#impact-score)

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## Description

The mpi\_powm function in Libgcrypt before 1.6.3 and GnuPG before 1.4.19
allows attackers to obtain sensitive information by leveraging timing
differences when accessing a pre-computed table during modular
exponentiation, related to a "Last-Level Cache Side-Channel Attack."

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| gnupg | 14.10 utopic | Fixed 1.4.16-1.2ubuntu1.2 |
| 14.04 LTS trusty | Fixed 1.4.16-1ubuntu2.3 |
| 12.04 LTS precise | Fixed 1.4.11-3ubuntu2.9 |
| 10.04 LTS lucid | Fixed 1.4.10-2ubuntu1.8 |
| libgcrypt11 | 14.10 utopic | Fixed 1.5.4-2ubuntu1.1 |
| 14.04 LTS trusty | Fixed 1.5.3-2ubuntu4.2 |
| 12.04 LTS precise | Fixed 1.5.0-3ubuntu0.4 |
| 10.04 LTS lucid | Fixed 1.4.4-5ubuntu2.4 |
| libgcrypt20 | 14.10 utopic | Fixed 1.6.1-2ubuntu1.14.10.1 |
| 14.04 LTS trusty | Fixed 1.6.1-2ubuntu1.14.04.1 |
| 12.04 LTS precise | Not in release |
| 10.04 LTS lucid | 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-2015-0837?format=md#patch-details)

### 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 |
| --- | --- |
| gnupg | * Upstream:   <http://git.gnupg.org/cgi-bin/gitweb.cgi?p=gnupg.git;a=commitdiff;h=6cbc75e71295f23431c4ab95edc7573f2fc28476> |
| libgcrypt20 | * Upstream:   <http://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git;a=commit;h=deb6f231ba85f65283c9e1deb3e2dea3b6ca46dc> * Upstream:   <http://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git;a=commit;h=d9f002899d26dc64f1502ae5050632340a4780fe> * Upstream:   <http://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git;a=commit;h=5e72b6c76ebee720f69b8a5c212f52d38eb50287> |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

5.9 · Medium

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Network |
  | Attack complexity | High |
  | Privileges required | None |
  | User interaction | None |
  | Scope | Unchanged |
  | Confidentiality impact | High |
  | Integrity impact | None |
  | Availability impact | None |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 5.9 · Medium |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-0837)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2015-0837)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2015-0837)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2015-0837)

### Related Ubuntu Security Notices (USN)

+ [USN-2555-1](https://usn.ubuntu.com/USN-2555-1)
+ Libgcrypt vulnerabilities
+ 1 April 2015

+ [USN-2554-1](https://usn.ubuntu.com/USN-2554-1)
+ GnuPG vulnerabilities
+ 1 April 2015

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2015-0837>