Information disclosure in Nextcloud Richdocuments

CVE-2021-39223

Nextcloud is an open-source, self-hosted productivity platform. The Nextcloud Richdocuments application prior to versions 3.8.6 and 4.2.3 returned verbatim exception messages to the user. This could result in a full path disclosure on shared files. (e.g. an attacker could see that the file `shared.txt` is located within `/files/$username/Myfolder/Mysubfolder/shared.txt`). It is recommended that the Richdocuments application is upgraded to 3.8.6 or 4.2.3. As a workaround, disable the Richdocuments application in the app settings.

Vulnerability class: Information Disclosure

EPSS: 0.010 (59.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-39223?
CVE-2021-39223 is a medium-severity vulnerability in Nextcloud Richdocuments, classified under Information Disclosure. CVSS score: 4.8/10. Published 2021-10-25.
How severe is CVE-2021-39223?
Medium severity. CVSS v3 base score is 4.8 out of 10.