What is CVE-2018-20827?

CVE-2018-20827 is a medium-severity vulnerability in Atlassian Jira, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2019-08-09.

How severe is CVE-2018-20827?

Medium severity. CVSS v3 base score is 5.4 out of 10.

XSS in Atlassian Jira

CVE-2018-20827

The activity stream gadget in Jira before version 7.13.1 allows remote attackers to inject arbitrary HTML or JavaScript via a cross site scripting (XSS) vulnerability in the country parameter.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2019-08-09 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.008 (53.5th percentile), scored 2026-10-02.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 53rd percentile — 53.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000

Affected products

Atlassian Jira — versions unspecified

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

jira.atlassian.com/browse/JRASERVER-69237 (Exploit, Issue Tracking, Vendor Advisory)

Frequently asked questions

What is CVE-2018-20827?: CVE-2018-20827 is a medium-severity vulnerability in Atlassian Jira, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2019-08-09.
How severe is CVE-2018-20827?: Medium severity. CVSS v3 base score is 5.4 out of 10.