How severe is CVE-2023-45150?

CVE-2023-45150 has a CVSS 3.x base score of 4.3, 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 none, and availability low.

Is CVE-2023-45150 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-45150?

CVE-2023-45150 affects Nextcloud Calendar. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-45150?

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

When was CVE-2023-45150 published?

CVE-2023-45150 was published on 2023-10-16 and last updated on 2026-06-17.

CVE-2023-45150

CVE-2023-45150 is a medium-severity vulnerability in Nextcloud Calendar with a CVSS 3.x base score of 4.3. 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-354.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
EPSS exploit prediction: 0% (31st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-354
Affected product: Nextcloud Calendar
Published: 2023-10-16
Last modified: 2026-06-17

Description

Nextcloud calendar is a calendar app for the Nextcloud server platform. Due to missing precondition checks the server was trying to validate strings of any length as email addresses even when megabytes of data were provided, eventually making the server busy and unresponsive. It is recommended that the Nextcloud Calendar app is upgraded to 4.4.4. The only workaround for users unable to upgrade is to disable the calendar app.

Frequently asked questions

What is CVE-2023-45150?: Nextcloud calendar is a calendar app for the Nextcloud server platform. Due to missing precondition checks the server was trying to validate strings of any length as email addresses even when megabytes of data were provided, eventually making the server busy and unresponsive. It is recommended that the Nextcloud Calendar app is upgraded to 4.4.4. The only workaround for users unable to upgrade is to disable the calendar app.
How severe is CVE-2023-45150?: CVE-2023-45150 has a CVSS 3.x base score of 4.3, 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 none, and availability low.
Is CVE-2023-45150 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-45150?: CVE-2023-45150 affects Nextcloud Calendar. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-45150?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-45150 published?: CVE-2023-45150 was published on 2023-10-16 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:nextcloud:calendar:*:*:*:*:*:*:*:*

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