---
title: "CVE-2017-16853\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-2017-16853?format=md
keywords: index, follow
---

# CVE-2017-16853

Publication date 16 November 2017

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**8.1 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2017-16853?format=md#impact-score)

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## Description

The DynamicMetadataProvider class in
saml/saml2/metadata/impl/DynamicMetadataProvider.cpp in OpenSAML-C in
OpenSAML before 2.6.1 fails to properly configure itself with the
MetadataFilter plugins and does not perform critical security checks such
as signature verification, enforcement of validity periods, and other
checks specific to deployments, aka CPPOST-105.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| opensaml2 | 18.10 cosmic | Not affected |
| 18.04 LTS bionic | Not affected |
| 17.10 artful | Fixed 2.6.0-4+deb9u1build0.17.10.1 |
| 17.04 zesty | Fixed 2.6.0-4+deb9u1build0.17.04.1 |
| 16.04 LTS xenial | Fixed 2.5.5-1ubuntu0.1 |
| 14.04 LTS trusty | Fixed 2.5.3-2+deb8u2build0.14.04.1 |

---

* [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**

8.1 · High

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 8.1 · High |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-16853)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2017-16853)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2017-16853)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2017-16853)

### Other references

* <https://git.shibboleth.net/view/?p=cpp-opensaml.git;a=commit;h=6182b0acf2df670e75423c2ed7afe6950ef11c9d>
* <https://shibboleth.net/community/advisories/secadv_20171115.txt>
* <https://bugs.debian.org/881856>
* <https://www.cve.org/CVERecord?id=CVE-2017-16853>