How severe is CVE-2023-49791?

CVE-2023-49791 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability low.

Is CVE-2023-49791 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-49791?

CVE-2023-49791 primarily affects Nextcloud Nextcloud Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-49791?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-49791 published?

CVE-2023-49791 was published on 2023-12-22 and last updated on 2026-06-17.

CVE-2023-49791

CVE-2023-49791 is a medium-severity vulnerability in Nextcloud Nextcloud Server with a CVSS 3.x base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-284.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
EPSS exploit prediction: 1% (45th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-284
Affected product: Nextcloud Nextcloud Server
Published: 2023-12-22
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2023-49791?: 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.
How severe is CVE-2023-49791?: CVE-2023-49791 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability low.
Is CVE-2023-49791 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-49791?: CVE-2023-49791 primarily affects Nextcloud Nextcloud Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-49791?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-49791 published?: CVE-2023-49791 was published on 2023-12-22 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:enterprise:*:*:*
cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:-:*:*:*

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