Vulnerability in Redmine

CVE-2021-31864

Redmine before 4.0.9, 4.1.x before 4.1.3, and 4.2.x before 4.2.1 allows attackers to bypass the add_issue_notes permission requirement by leveraging the incoming mail handler.

Published 2021-04-28 · 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:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.012 (66.8th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 67th percentile — 66.8% 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

Redmine
Debian Linux — versions 9.0

References

www.redmine.org/projects/redmine/wiki/Security_Advisories (Vendor Advisory)
www.redmine.org/news/131 (Vendor Advisory)
lists.debian.org/debian-lts-announce/2021/05/msg00013.html (mailing-list, Mailing List, Third Party Advisory)

Frequently asked questions

What is CVE-2021-31864?: CVE-2021-31864 is a medium-severity vulnerability in Redmine. CVSS score: 5.3/10. Published 2021-04-28.
How severe is CVE-2021-31864?: Medium severity. CVSS v3 base score is 5.3 out of 10.