---
title: "CVE-2019-11356\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-2019-11356?format=md
keywords: index, follow
---

# CVE-2019-11356

Publication date 3 June 2019

Last updated 25 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-2019-11356?format=md#impact-score)

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## Description

The CalDAV feature in httpd in Cyrus IMAP 2.5.x through 2.5.12 and 3.0.x
through 3.0.9 allows remote attackers to execute arbitrary code via a
crafted HTTP PUT operation for an event with a long iCalendar property
name.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| cyrus-imapd | 20.10 groovy | Fixed 3.0.8-6 |
| 20.04 LTS focal | Fixed 3.0.8-6 |
| 19.10 eoan | Fixed 3.0.8-6 |
| 19.04 disco | Ignored end of life |
| 18.10 cosmic | Ignored end of life |
| 18.04 LTS bionic | Fixed 2.5.10-3ubuntu1.1 |
| 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)

## 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-2019-11356)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2019-11356)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2019-11356)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2019-11356)

### Related Ubuntu Security Notices (USN)

+ [USN-4566-1](https://usn.ubuntu.com/USN-4566-1)
+ Cyrus IMAP Server vulnerabilities
+ 5 October 2020

### Other references

* <https://bugzilla.redhat.com/show_bug.cgi?id=1717828>
* <https://github.com/cyrusimap/cyrus-imapd/commit/a5779db8163b99463e25e7c476f9cbba438b65f3>
* <https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/IGO43JS7IFDNITHXOOHOP6JHRKRDIYY6/>
* <https://www.cyrusimap.org/imap/download/release-notes/2.5/index.html>
* <https://www.cyrusimap.org/imap/download/release-notes/2.5/x/2.5.13.html>
* <https://www.cyrusimap.org/imap/download/release-notes/3.0/index.html>
* <https://www.cyrusimap.org/imap/download/release-notes/3.0/x/3.0.10.html>
* <https://www.cve.org/CVERecord?id=CVE-2019-11356>