What is CVE-2020-8122?

CVE-2020-8122 is a medium-severity vulnerability in Nextcloud Server, classified under Improper Access Control. CVSS score: 4.3/10. Published 2020-02-04.

How severe is CVE-2020-8122?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Improper input validation in Nextcloud Server

CVE-2020-8122

A missing check in Nextcloud Server 14.0.3 could give recipient the possibility to extend the expiration date of a share they received.

Published 2020-02-04 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.007 (50.7th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 51st percentile — 50.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000

Affected products

Nextcloud Server
Nextcloud Server — versions 14.0.4

Weakness classification (CWE)

References

hackerone.com/reports/447494 (Exploit, Third Party Advisory)
nextcloud.com/security/advisory/ (Vendor Advisory)

Frequently asked questions

What is CVE-2020-8122?: CVE-2020-8122 is a medium-severity vulnerability in Nextcloud Server, classified under Improper Access Control. CVSS score: 4.3/10. Published 2020-02-04.
How severe is CVE-2020-8122?: Medium severity. CVSS v3 base score is 4.3 out of 10.