CVE-2023-49791: Workflows do not require password confirmation on API level

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-12-22 · updated 2026-06-17
Weakness: CWE-284

Description

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. In Nextcloud Server prior to versions 26.0.9 and 27.1.4; as well as Nextcloud Enterprise Server prior to versions 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4; when an attacker manages to get access to an active session of another user via another way, they could delete and modify workflows by sending calls directly to the API bypassing the password confirmation shown in the UI. Nextcloud Server versions 26.0.9 and 27.1.4 and Nextcloud Enterprise Server versions 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4 contain a patch for this issue. No known workarounds are available.

Affected products

Nextcloud Server: from 23.0.0 before 23.0.12.13; from 24.0.0 before 24.0.12.9; from 25.0.0 before 25.0.13.4; from 26.0.0 before 26.0.9; from 27.0.0 before 27.1.4 — fixed in 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, 27.1.4

How to fix

Upgrade to a fixed version: Nextcloud Server 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9. Check the vendor advisory for mitigations.

References

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