What is CVE-2020-8278?

CVE-2020-8278 is a medium-severity vulnerability in Nextcloud Social, classified under Improper Access Control. CVSS score: 5.3/10. Published 2020-11-19.

How severe is CVE-2020-8278?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Auth bypass in Nextcloud Social

CVE-2020-8278

Improper access control in Nextcloud Social app version 0.3.1 allowed to read posts of any user.

Published 2020-11-19 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.010 (61.9th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 62nd percentile — 61.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: 0.000

Affected products

Nextcloud Social — versions 0.3.1
Nextcloud Social — versions Affects v0.3.1, Fixed in v0.4.0

Weakness classification (CWE)

References

hackerone.com/reports/921717 (Exploit, Third Party Advisory)
nextcloud.com/security/advisory/ (Product, Broken Link)

Frequently asked questions

What is CVE-2020-8278?: CVE-2020-8278 is a medium-severity vulnerability in Nextcloud Social, classified under Improper Access Control. CVSS score: 5.3/10. Published 2020-11-19.
How severe is CVE-2020-8278?: Medium severity. CVSS v3 base score is 5.3 out of 10.