CVE-2023-45150: Inviting excessive long email addresses to a calendar event makes the Nextcloud server unresponsive

Published Oct 16, 2023
·
Updated

Nextcloud calendar is a calendar app for the Nextcloud server platform. Due to missing precondition checks the server was trying to validate strings of any length as email addresses even when megabytes of data were provided, eventually making the server busy and unresponsive. It is recommended that the Nextcloud Calendar app is upgraded to 4.4.4. The only workaround for users unable to upgrade is to disable the calendar app.

Affected Software

1 affected component
Nextcloud calendar>=1.0<4.4.4

Event History

Oct 16, 2023
CVE Published
via MITRE·07:06 PM
Data Sourced
via MITRE·07:06 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is CVE-2023-45150?

CVE-2023-45150 is a vulnerability in the Nextcloud calendar app that allows an attacker to make the server unresponsive by providing large amounts of data.

2

What is the severity of CVE-2023-45150?

The severity of CVE-2023-45150 is medium, with a CVSS score of 4.3.

3

Which versions of Nextcloud calendar are affected by CVE-2023-45150?

Nextcloud calendar versions 1.0 to 4.4.4 are affected by CVE-2023-45150.

4

How can I fix CVE-2023-45150?

To fix CVE-2023-45150, you should update to a version of Nextcloud calendar that is not impacted by the vulnerability.

5

Where can I find more information about CVE-2023-45150?

You can find more information about CVE-2023-45150 in the provided references: [GitHub pull request](https://github.com/nextcloud/calendar/pull/5358), [Nextcloud security advisories](https://github.com/nextcloud/security-advisories/security/advisories/GHSA-r936-8gwm-w452), [HackerOne report](https://hackerone.com/reports/2058337).

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