CVE-2023-45150

Public Exploit
Inviting excessive long email addresses to a calendar event makes the Nextcloud server unresponsive

Description

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.

Categories

4.3
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.12%
Vendor Advisory github.com
Affected: nextcloud security-advisories
Published at:
Updated at:

References

Link Tags
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-r936-8gwm-w452 vendor advisory
https://github.com/nextcloud/calendar/pull/5358 patch
https://hackerone.com/reports/2058337 issue tracking exploit

Frequently Asked Questions

What is the severity of CVE-2023-45150?
CVE-2023-45150 has been scored as a medium severity vulnerability.
How to fix CVE-2023-45150?
To fix CVE-2023-45150, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-45150 being actively exploited in the wild?
It is possible that CVE-2023-45150 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-45150?
CVE-2023-45150 affects nextcloud security-advisories.
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