What is CVE-2018-3775?

CVE-2018-3775 is a high-severity vulnerability in HackerOne Nextcloud Server, classified under Improper Authentication. CVSS score: 8.8/10. Published 2018-08-12.

How severe is CVE-2018-3775?

High severity. CVSS v3 base score is 8.8 out of 10.

Auth bypass in HackerOne Nextcloud Server

CVE-2018-3775

Improper Authentication in Nextcloud Server prior to version 12.0.3 would allow an attacker that obtained user credentials to bypass the 2 Factor Authentication.

Vulnerability class: Broken Authentication

Published 2018-08-12 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.012 (68.5th percentile), scored 2026-10-19.

Low probability of exploitation in the next 30 days, but still tracked. 69th percentile — 68.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.012 · newest: 0.012 · change: 0.000

Affected products

HackerOne Nextcloud Server — versions <12.0.3
Nextcloud Server

Weakness classification (CWE)

CWE-287 — Improper Authentication

References

nextcloud.com/security/advisory/ (Broken Link, Vendor Advisory)
hackerone.com/reports/248656 (Third Party Advisory, Issue Tracking)

Frequently asked questions

What is CVE-2018-3775?: CVE-2018-3775 is a high-severity vulnerability in HackerOne Nextcloud Server, classified under Improper Authentication. CVSS score: 8.8/10. Published 2018-08-12.
How severe is CVE-2018-3775?: High severity. CVSS v3 base score is 8.8 out of 10.