CVE-2024-52523: Nextcloud Server Custom defined credentials of external storages are sent back to the frontend

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-11-15 · updated 2026-06-17
Weakness: CWE-200

Description

Nextcloud Server is a self hosted personal cloud system. After setting up a user or administrator defined external storage with fixed credentials, the API returns them and adds them into the frontend again, allowing to read them in plain text when an attacker already has access to an active session of a user. It is recommended that the Nextcloud Server is upgraded to 28.0.12, 29.0.9 or 30.0.2 and Nextcloud Enterprise Server is upgraded to 25.0.13.14, 26.0.13.10, 27.1.11.10, 28.0.12, 29.0.9 or 30.0.2.

Affected products

Nextcloud Server: from 25.0.0 before 25.0.13.14; from 26.0.0 before 26.0.13.10; from 27.0.0 before 27.1.11.10; from 28.0.0 before 28.0.12; from 29.0.0 before 29.0.9; from 30.0.0 before 30.0.2 — fixed in 25.0.13.14, 26.0.13.10, 27.1.11.10, 28.0.12, 29.0.9, 30.0.2

How to fix

Upgrade to a fixed version: Nextcloud Server 25.0.13.14, 26.0.13.10, 27.1.11.10, 28.0.12. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2024-52523 or the next vulnerability affects your stack