ReviewHigh

CVE-2026-21582

Atlassian Crowd Data Center

This High severity BASM (Broken Authentication & Session Management) vulnerability known as CVE-2026-21582 was introduced in version 7.2.1 of Crowd Data Center. This BASM (Broken Authentication & Session Management) vulnerability, with a CVSS Score of 8.8, allows an unauthenticated attacker to perform actions as another user. Atlassian recommends that Crowd Data Center 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 7.2: Upgrade to a release greater than or equal to 7.2.2 See the relea...

CVSS: 8.8
EPSS: 0.39%
CISA KEV: Not listed
Published: 2026.08.19

PRIORITY ASSESSMENT

Review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.39%

Technical severityCVSS 8.8

Vulnerability overview

Affected product and versions

Product: Atlassian Crowd Data Center
Affected versions: >= 7.2.1
Fixed versions: No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that Atlassian Crowd Data Center and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CWE: CWE-287