How severe is CVE-2023-33183?

CVE-2023-33183 has a CVSS 3.x base score of 2.6, rated low severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2023-33183 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-33183?

CVE-2023-33183 affects Nextcloud Calendar. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-33183?

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

When was CVE-2023-33183 published?

CVE-2023-33183 was published on 2023-05-30 and last updated on 2026-06-17.

CVE-2023-33183

CVE-2023-33183 is a low-severity vulnerability in Nextcloud Calendar with a CVSS 3.x base score of 2.6. 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-285.

Key facts

Severity: Low (CVSS 3.x base score 2.6)
EPSS exploit prediction: 0% (35th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-285
Affected product: Nextcloud Calendar
Published: 2023-05-30
Last modified: 2026-06-17

Description

Calendar app for Nextcloud easily sync events from various devices with your Nextcloud. Some internal paths of the website are disclosed when the SMTP server is unavailable. It is recommended that the Calendar app is updated to 3.5.5 or 4.2.3

Frequently asked questions

What is CVE-2023-33183?: Calendar app for Nextcloud easily sync events from various devices with your Nextcloud. Some internal paths of the website are disclosed when the SMTP server is unavailable. It is recommended that the Calendar app is updated to 3.5.5 or 4.2.3
How severe is CVE-2023-33183?: CVE-2023-33183 has a CVSS 3.x base score of 2.6, rated low severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2023-33183 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-33183?: CVE-2023-33183 affects Nextcloud Calendar. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-33183?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-33183 published?: CVE-2023-33183 was published on 2023-05-30 and last updated on 2026-06-17.

References

Affected products (1)

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

More vulnerabilities in Nextcloud Calendar

CVE-2025-66550 — Medium (CVSS 5.7): Nextcloud Calendar is a calendar app for Nextcloud. Prior to 4.7.17 and 5.2.4, when a malicious user creates a calendar…
CVE-2022-24838 — Medium (CVSS 5.3): Nextcloud Calendar is a calendar application for the nextcloud framework. SMTP Command Injection in Appointment Emails…
CVE-2025-66511 — Medium (CVSS 4.8): Nextcloud Calendar is a calendar app for Nextcloud. Prior to 6.0.3, the Calendar app generates participant tokens for…
CVE-2018-3763 — Medium (CVSS 4.8): In Nextcloud Calendar before 1.5.8 and 1.6.1, a missing sanitization of search results for an autocomplete field could…
CVE-2024-37316 — Medium (CVSS 4.6): Nextcloud Calendar is a calendar app for Nextcloud. Authenticated users could create an event with manipulated…
CVE-2026-45286 — Medium (CVSS 4.3): Nextcloud is an open source content collaboration platform. From versions 5.5.13 to before 5.5.17, and 6.2.0 to before…

All CVEs affecting Nextcloud Calendar →

Other CWE-285 (Improper Authorization) vulnerabilities

CVE-2025-65041 — Critical (CVSS 10.0): Improper authorization in Microsoft Partner Center allows an unauthorized attacker to elevate privileges over a network.
CVE-2023-33189 — Critical (CVSS 10.0): Pomerium is an identity and context-aware access proxy. With specially crafted requests, incorrect authorization…
CVE-2022-2595 — Critical (CVSS 10.0): Improper Authorization in GitHub repository kromitgmbh/titra prior to 0.79.1.
CVE-2021-28799 — Critical (CVSS 10.0): An improper authorization vulnerability has been reported to affect QNAP NAS running HBS 3 (Hybrid Backup Sync. ) If…
CVE-2026-34048 — Critical (CVSS 9.9): Coolify is an open-source and self-hostable tool for managing servers, applications, and databases. Prior to…
CVE-2026-5412 — Critical (CVSS 9.9): In Juju versions prior to 2.9.57 and 3.6.21, an authorization issue exists in the Controller facade. An authenticated…

Browse all CWE-285 (Improper Authorization) vulnerabilities →