Vulnerability · Published Aug 18, 2026 · Assigned by atlassian
CVE-2026-21582
High 8.8
In plain English
A high-severity improper authentication in Crowd Data Center from Atlassian. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 40% of all known vulnerabilities).
Official description
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 release notes (https://confluence.atlassian.com/crowd/crowd-release-notes-199094.html). You can download the latest version of Crowd Data Center from the download center (https://www.atlassian.com/software/crowd/download-archive). This vulnerability was reported via our Penetration Testing program.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Atlassian | Crowd Data Center | 7.2.1 |
Weakness: CWE-287 · 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