CVE-2023-39959

Existence of calendars and address books can be checked by unauthenticated users

Description

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 25.0.0 and prior to versions 25.0.9, 26.0.4, and 27.0.1, unauthenticated users could send a DAV request which reveals whether a calendar or an address book with the given identifier exists for the victim. Nextcloud Server versions 25.0.9, 26.0.4, and 27.0.1 and Nextcloud Enterprise Server versions 25.0.9, 26.0.4, and 27.0.1 contain a patch for this issue. No known workarounds are available.

Category

3.5
CVSS
Severity: Low
CVSS 3.1 •
EPSS 0.66%
Vendor Advisory github.com
Affected: nextcloud security-advisories
Published at:
Updated at:

References

Link Tags
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-g97r-8ffm-hfpj vendor advisory
https://github.com/nextcloud/server/pull/38747 patch
https://hackerone.com/reports/1832126 permissions required

Frequently Asked Questions

What is the severity of CVE-2023-39959?
CVE-2023-39959 has been scored as a low severity vulnerability.
How to fix CVE-2023-39959?
To fix CVE-2023-39959, 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-2023-39959 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-39959 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-39959?
CVE-2023-39959 affects nextcloud security-advisories.
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