What is CVE-2019-15612?

CVE-2019-15612 is a medium-severity vulnerability in Nextcloud Server, classified under Session Fixation. CVSS score: 5.9/10. Published 2020-02-04.

How severe is CVE-2019-15612?

Medium severity. CVSS v3 base score is 5.9 out of 10.

Vulnerability in Nextcloud Server

CVE-2019-15612

A bug in Nextcloud Server 15.0.2 causes pending 2FA logins to not be correctly expired when the password of the user is reset.

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

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:P/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.003 (22.5th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 22nd percentile — 22.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Nextcloud Server
Nextcloud Server — versions 15.0.3

Weakness classification (CWE)

CWE-384 — Session Fixation

References

hackerone.com/reports/486693 (Permissions Required, Third Party Advisory)
nextcloud.com/security/advisory/ (Vendor Advisory)

Frequently asked questions

What is CVE-2019-15612?: CVE-2019-15612 is a medium-severity vulnerability in Nextcloud Server, classified under Session Fixation. CVSS score: 5.9/10. Published 2020-02-04.
How severe is CVE-2019-15612?: Medium severity. CVSS v3 base score is 5.9 out of 10.