Uncontrolled resource consumption in Atlassian Confluence Data Center
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-400.
Summary
This High severity DoS (Denial of Service) vulnerability was introduced in versions 9.0.1, 9.1.0, 9.2.0, 9.3.1, 9.4.0, 9.5.1, 10.0.2, 10.1.0 and 10.2.0 of Confluence Data Center. This DoS (Denial of Service) vulnerability, with a CVSS Score of 7.1, allows an authenticated attacker to cause a resource to be unavailable for its intended users by temporarily or indefinitely disrupting services of a host connected to a network. Atlassian recommends that Confluence 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: Confluence Data Center 9.2: Upgrade to a release greater than or equal to 9.2.17 Confluence Data Center 10.2: Upgrade to a release greater than or equal to 10.2.7 See the release notes ([https://confluence.atlassian.com/doc/confluence-release-notes-327.html]). You can download the latest version of Confluence Data Center from the download center ([https://www.atlassian.com/software/confluence/download-archives]). This vulnerability was reported via our Penetration Testing program.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Atlassian | Confluence Data Center | 10.2.0 to 10.2.6; 10.1.0 to 10.1.2; 10.0.2 to 10.0.3; 9.5.1 to 9.5.4; 9.4.0 to 9.4.1; 9.3.1 to 9.3.2; 9.2.0 to 9.2.15; 9.1.0 to 9.1.1; 9.0.1 to 9.0.3 | 10.2.7 to 10.2.14, 9.2.17 to 9.2.22 | Patch available | CNA |
- Confluence Data Center VendorAtlassian Affected 10.2.0 to 10.2.6; 10.1.0 to 10.1.2; 10.0.2 to 10.0.3; 9.5.1 to 9.5.4; 9.4.0 to 9.4.1; 9.3.1 to 9.3.2; 9.2.0 to 9.2.15; 9.1.0 to 9.1.1; 9.0.1 to 9.0.3 Fixed in 10.2.7 to 10.2.14, 9.2.17 to 9.2.22 Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:atlassian:confluence_data_center:*:*:*:*:*:*:*:* | 9.0.1 – 9.0.3; 9.1.0 – 9.1.1; 9.2.0 – 9.2.15; 9.3.1 – 9.3.2; 9.4.0 – 9.4.1; 9.5.1 – 9.5.4; 10.0.2 – 10.0.3; 10.1.0 – 10.1.2; 10.2.0 – 10.2.6 | Vulnerable | Atlassian |
- cpe:2.3:a:atlassian:confluence_data_center:*:*:*:*:*:*:*:* Versions 9.0.1 – 9.0.3; 9.1.0 – 9.1.1; 9.2.0 – 9.2.15; 9.3.1 – 9.3.2; 9.4.0 – 9.4.1; 9.5.1 – 9.5.4; 10.0.2 – 10.0.3; 10.1.0 – 10.1.2; 10.2.0 – 10.2.6 Vulnerable ·Atlassian
Remediation
- Fix · CNA Confluence Data Center (Atlassian) Fixed in 10.2.7 to 10.2.14, 9.2.17 to 9.2.22
Timeline
- 2026-10-02 Threatist record created from CVE-2026-21577
- 2026-10-03 Alias added: GHSA-2v44-87c2-pxr3
References
More Atlassian Confluence Data Center vulnerabilities
- TI-2023-08765 Injection in Atlassian Confluence Data Center KEVCVSS 3.1CRITICAL 9.8
- TI-2023-08757 Improper input validation in Atlassian Confluence Data Center KEVCVSS 3.1CRITICAL 9.8
- TI-2022-09596 Expression language injection in Atlassian Confluence Data Center KEVCVSS 3.1CRITICAL 9.8
- TI-2021-08036 Expression language injection in Atlassian Confluence Server KEVCVSS 3.1CRITICAL 9.8
- TI-2026-67904 Arbitrary file access in Atlassian Data Center products KEVCVSS 4.0CRITICAL 9.3
- TI-2023-08759 Incorrect authorization in Atlassian Confluence Data Center KEVCVSS 3.1CRITICAL 9.8
Sources
- CVE-2026-21577 · CVE Program
- CVE-2026-21577 · NVD
- FIRST EPSS
- GHSA-2v44-87c2-pxr3 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences