How severe is CVE-2023-32320?

CVE-2023-32320 has a CVSS 3.x base score of 8.7, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2023-32320 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-32320?

CVE-2023-32320 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-2023-32320?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2023-32320 published?

CVE-2023-32320 was published on 2023-06-22 and last updated on 2026-06-17.

CVE-2023-32320

CVE-2023-32320 is a high-severity vulnerability in Nextcloud Nextcloud Server with a CVSS 3.x base score of 8.7. 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-307.

Key facts

Severity: High (CVSS 3.x base score 8.7)
EPSS exploit prediction: 1% (55th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-307
Affected product: Nextcloud Nextcloud Server
Published: 2023-06-22
Last modified: 2026-06-17

Description

Nextcloud Server is a data storage system for Nextcloud, a self-hosted productivity platform. When multiple requests are sent in parallel, all of them were executed even if the amount of faulty requests succeeded the limit by the time the response was sent to the client. This allowed someone to send as many requests the server could handle in parallel to bruteforce protected details instead of the configured limit, default 8. Nextcloud Server versions 25.0.7 and 26.0.2 and Nextcloud Enterprise Server versions 21.0.9.12, 22.2.10.12, 23.0.12.7, 24.0.12.2, 25.0.7 and 26.0.2 contain patches for this issue.

Frequently asked questions

What is CVE-2023-32320?: Nextcloud Server is a data storage system for Nextcloud, a self-hosted productivity platform. When multiple requests are sent in parallel, all of them were executed even if the amount of faulty requests succeeded the limit by the time the response was sent to the client. This allowed someone to send as many requests the server could handle in parallel to bruteforce protected details instead of the configured limit, default 8. Nextcloud Server versions 25.0.7 and 26.0.2 and Nextcloud Enterprise Server versions 21.0.9.12, 22.2.10.12, 23.0.12.7, 24.0.12.2, 25.0.7 and 26.0.2 contain patches for this issue.
How severe is CVE-2023-32320?: CVE-2023-32320 has a CVSS 3.x base score of 8.7, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2023-32320 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-32320?: CVE-2023-32320 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-2023-32320?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-32320 published?: CVE-2023-32320 was published on 2023-06-22 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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