CVE-2026-21587 json
This High severity Improper Authorization vulnerability was introduced in version 11.3.0 of Jira Service Management Data Center.
published 2026-09-15 54 d ago modified 2026-09-17 53 d ago also EUVD-2026-78936
- cvss
- 7.1
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 38%
- public exploits
- 0
- none known
Summary
This High severity Improper Authorization vulnerability was introduced in version 11.3.0 of Jira Service Management Data Center.
This Improper Authorization vulnerability, with a CVSS Score of 7.1, allows an authenticated attacker to gain unintended access and can lead to the exposure of resources or functionality, possibly providing attackers with sensitive information or even execute arbitrary code.
Atlassian recommends that Jira Service Management 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:
* Jira Service Management Data Center 11.3: Upgrade to a release greater than or equal to 11.3.11
See the release notes (https://confluence.atlassian.com/servicemanagement/jira-service-management-release-notes-780083086.html). You can download the latest version of Jira Service Management Data Center from the download center (https://www.atlassian.com/software/jira/service-management/download-archives).
This vulnerability was reported via our Penetration Testing program.
Patch / fix
- Atlassian Jira Service Management Data Center 11.3.11
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 54 d ago
Exploit prediction
0.45% chance of exploitation in the next 30 days, higher than 38% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 7.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N |
| CNA | 4.0 | 7.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/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 |
Affected products
- Atlassian Jira Service Management Data Center
Classification
- Weakness
-
- CWE-285 Improper Authorization
References
Sources
- CVE List CVE-2026-21587
- NVD CVE-2026-21587
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.