What is CVE-2021-39123?

CVE-2021-39123 is a high-severity vulnerability in Atlassian Data Center. CVSS score: 7.5/10. Published 2021-09-14.

How severe is CVE-2021-39123?

High severity. CVSS v3 base score is 7.5 out of 10.

Vulnerability in Atlassian Data Center

CVE-2021-39123

Affected versions of Atlassian Jira Server and Data Center allow unauthenticated remote attackers to impact the application's availability via a Denial of Service (DoS) vulnerability in the /rest/gadget/1.0/createdVsResolved/generate endpoint. The affected versions are before version 8.16.0.

Published 2021-09-14 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.016 (75.8th percentile), scored 2026-11-01.

Low probability of exploitation in the next 30 days, but still tracked. 76th percentile — 75.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.016 · newest: 0.016 · change: 0.000

Affected products

Atlassian Data Center
Atlassian Jira
Atlassian Jira Data Center — versions unspecified
Atlassian Jira Server — versions unspecified

References

jira.atlassian.com/browse/JRASERVER-72237 (Third Party Advisory)

Frequently asked questions

What is CVE-2021-39123?: CVE-2021-39123 is a high-severity vulnerability in Atlassian Data Center. CVSS score: 7.5/10. Published 2021-09-14.
How severe is CVE-2021-39123?: High severity. CVSS v3 base score is 7.5 out of 10.