Quick answers
- Is CVE-2026-21587 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-21587 being exploited in the wild.
- How severe is CVE-2026-21587?
- Informational severity, with a CVSS score of 7.1, published 15 September 2026.
- Which products and versions are affected?
- Atlassian Jira Service Management Data Center 11.3.0 to 11.3.10.
- Is there a fix for CVE-2026-21587?
- A patch was published on 2026-09-15: Fixed in version 11.3.11 and later Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-21587 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-21587?
- Check whether you run Atlassian Jira Service Management Data Center at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
This improper authorization vulnerability in Jira Service Management Data Center was introduced in version 11.3.0 and affects versions 11.3.0 through 11.3.10. The flaw allows an authenticated attacker to bypass access controls and gain unintended access to resources or functionality. The vulnerability requires network access and prior authentication but does not require user interaction. An attacker can exploit this to access sensitive information or potentially execute arbitrary code. The fix is available in version 11.3.11 and later.
Affected products
- Atlassian Jira Service Management Data Center 11.3.0 to 11.3.10
Timeline
- 2026-09-15: disclosed
- 2026-09-15: patched: Fixed in version 11.3.11 and later