CVE-2023-48308 — Nextcloud/Cloud is a calendar app for Nextcloud

Nextcloud/Cloud is a calendar app for Nextcloud. An attacker can gain access to stacktrace and internal paths of the server when generating an exception while editing a calendar appointment. It is recommended that the Nextcloud Calendar app is upgraded to 4.5.3

01What is this vulnerability?

Nextcloud/Cloud is a calendar app for Nextcloud. An attacker can gain access to stacktrace and internal paths of the server when generating an exception while editing a calendar appointment. It is recommended that the Nextcloud Calendar app is upgraded to 4.5.3

02Affected products

Vendor	Product	Versions
nextcloud	security	advisories — >= 3.0.0, < 4.5.3

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2023-12-21T23:12:45.538Z
• Last modified: 2024-11-27T15:46:01.287Z

09References

• github.com — https://github.com/nextcloud/security-advisories/security/advisories/GHSA-fv3c-q…
• github.com — https://github.com/nextcloud/calendar/pull/5553