What is CVE-2026-21569?

CVE-2026-21569 is a high-severity vulnerability in Atlassian Crowd, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 7.9/10. Published 2026-01-28.

How severe is CVE-2026-21569?

High severity. CVSS v3 base score is 7.9 out of 10.

XXE in Atlassian Crowd

CVE-2026-21569

This High severity XXE (XML External Entity Injection) vulnerability was introduced in version 7.1.0 of Crowd Data Center and Server. This XXE (XML External Entity Injection) vulnerability, with a CVSS Score of 7.9, allows an authenticated attacker to access local and remote content which has high impact to confidentiality, low impact to integrity, high impact to availability, and requires no user interaction. Atlassian recommends that Crowd Data Center and Server customers upgrade to latest version, if you are unable to do so, upgrade your instance to one of the specified supported fixed versions: * Crowd Data Center and Server 7.1: Upgrade to a release greater than or equal to 7.1.3 See the release notes (https://confluence.atlassian.com/crowd/crowd-release-notes-199094.html). You can download the latest version of Crowd Data Center and Server from the download center (https://www.atlassian.com/software/crowd/download-archive). This vulnerability was reported via our Atlassian (Internal) program.

Vulnerability class: XXE (XML External Entity)

Published 2026-01-28 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.9 (High). Vector: CVSS:3.0/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:L/A:H.

EPSS exploit prediction

EPSS: 0.003 (25.2th percentile), scored 2026-10-19.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 25th percentile — 25.2% 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

Atlassian Crowd
Atlassian Crowd Data Center — versions 7.1.0 to 7.1.2, 7.1.3

Weakness classification (CWE)

CWE-611 — Improper Restriction of XML External Entity Reference (XXE)

References

confluence.atlassian.com/pages/viewpage.action (Vendor Advisory)
jira.atlassian.com/browse/CWD-6453 (Issue Tracking, Vendor Advisory)

Frequently asked questions

What is CVE-2026-21569?: CVE-2026-21569 is a high-severity vulnerability in Atlassian Crowd, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 7.9/10. Published 2026-01-28.
How severe is CVE-2026-21569?: High severity. CVSS v3 base score is 7.9 out of 10.