---
title: "CVE-2016-6298\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-2016-6298?format=md
keywords: index, follow
---

# CVE-2016-6298

Publication date 1 September 2016

Last updated 26 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**5.3 · Medium**

[Score breakdown](https://ubuntu.com/security/CVE-2016-6298?format=md#impact-score)

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## Description

The \_Rsa15 class in the RSA 1.5 algorithm implementation in jwa.py in
jwcrypto before 0.3.2 lacks the Random Filling protection mechanism, which
makes it easier for remote attackers to obtain cleartext data via a Million
Message Attack (MMA).

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| python-jwcrypto | 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 | Ignored end of life |
| 17.04 zesty | Ignored end of life |
| 16.10 yakkety | Ignored end of life |
| 16.04 LTS xenial | Vulnerable |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | 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)

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

5.3 · Medium

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Network |
  | 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 | 5.3 · Medium |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.1/AV:N/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-2016-6298)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2016-6298)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2016-6298)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2016-6298)

### Other references

* <https://github.com/latchset/jwcrypto/issues/65>
* <https://github.com/latchset/jwcrypto/pull/66>
* <https://github.com/latchset/jwcrypto/commit/eb5be5bd94c8cae1d7f3ba9801377084d8e5a7ba>
* <https://www.cve.org/CVERecord?id=CVE-2016-6298>