---
title: "CVE-2017-12621\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-2017-12621?format=md
keywords: index, follow
---

# CVE-2017-12621

Publication date 28 September 2017

Last updated 26 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**9.8 · Critical**

[Score breakdown](https://ubuntu.com/security/CVE-2017-12621?format=md#impact-score)

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## Description

During Jelly (xml) file parsing with Apache Xerces, if a custom doctype
entity is declared with a "SYSTEM" entity with a URL and that entity is
used in the body of the Jelly file, during parser instantiation the parser
will attempt to connect to said URL. This could lead to XML External Entity
(XXE) attacks in Apache Commons Jelly before 1.0.1.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2017-12621?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| jenkins-commons-jelly | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release |
| 25.04 plucky | Not in release |
| 24.10 oracular | Not in release |
| 24.04 LTS noble | Not in release |
| 23.10 mantic | Not in release |
| 22.04 LTS jammy | Not in release |
| 21.10 impish | Not in release |
| 21.04 hirsute | Not in release |
| 20.10 groovy | Not in release |
| 20.04 LTS focal | Not in release |
| 19.10 eoan | Not in release |
| 19.04 disco | Not in release |
| 18.10 cosmic | Not in release |
| 18.04 LTS bionic | Not in release |
| 17.10 artful | Not in release |
| 17.04 zesty | Not in release |
| 16.04 LTS xenial | Vulnerable |
| 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)

## Notes

---

### [msalvatore](https://launchpad.net/~msalvatore)

Eventhough the version of jenkins-commons-jelly in trusty and
xenial is 1.1, the fix is still needed.

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

9.8 · Critical

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 9.8 · Critical |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-12621)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2017-12621)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2017-12621)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2017-12621)

### Other references

* <http://www.openwall.com/lists/oss-security/2017/09/27/6>
* <https://www.cve.org/CVERecord?id=CVE-2017-12621>