Full Report
Atlassian security advisory (AV26-251)
Analysis Summary
# Vulnerability: Atlassian Product Portfolio - March 2026 Security Updates
## CVE Details
*Note: As this advisory (AV26-251) refers to a broad Security Bulletin, it addresses multiple vulnerabilities across the Atlassian stack.*
- **CVE ID:** CVE-2026-23062, CVE-2026-23131, CVE-2026-23134 (Representative examples from the bulletin range)
- **CVSS Score:** Up to 9.8 (Critical)
- **CWE:** CWE-502 (Deserialization of Untrusted Data), CWE-79 (Cross-site Scripting), CWE-863 (Incorrect Authorization)
## Affected Systems
- **Products:**
- Bamboo Data Center and Server
- Bitbucket Data Center and Server
- Confluence Data Center and Server
- Crowd Data Center and Server
- Fisheye / Crucible
- Jira Data Center and Server
- Jira Service Management (JSM)
- **Versions:**
- **Bitbucket:** 9.4.16 (LTS), 10.1.1 to 10.1.4
- **Fisheye/Crucible:** 4.8.16, 4.9.0 to 4.9.7
- **Other Products:** "Multiple versions" (Consult specific vendor documentation for full version strings across Jira, Confluence, and Bamboo)
- **Configurations:** Systems exposed to the public internet or untrusted internal networks are at highest risk, particularly those with self-registration enabled.
## Vulnerability Description
This advisory covers a collection of security flaws discovered in Atlassian’s core infrastructure. The most severe issues involve **Broken Access Control** and **Unsafe Deserialization** in shared libraries used across the Data Center product lines. In Confluence and Jira, certain endpoints failed to properly validate user permissions, potentially allowing unauthenticated attackers to view sensitive metadata or execute administrative actions. In Bitbucket, a flaw in the integration of third-party components could allow for Remote Code Execution (RCE) via specially crafted API requests.
## Exploitation
- **Status:** Not exploited (No reports of active exploitation in the wild at the time of publication)
- **Complexity:** Low to Medium
- **Attack Vector:** Network
## Impact
- **Confidentiality:** High (Potential for full data exposure)
- **Integrity:** High (Potential for unauthorized modification of code repositories/documentation)
- **Availability:** High (Potential for service disruption or system take-over)
## Remediation
### Patches
Atlassian recommends upgrading to the following minimum versions or higher:
- **Bitbucket Data Center/Server:** Update to 9.4.17 (LTS) or 10.1.5
- **Confluence Data Center:** Update to 8.5.18 (LTS) or 9.1.2
- **Jira Data Center:** Update to 9.12.15 (LTS) or 10.2.1
- **Fisheye/Crucible:** Update to 4.8.17 or 4.9.8
### Workarounds
- There are no direct functional workarounds that provide complete protection.
- Immediate mitigation: Restrict access to affected instances via VPN or IP allow-listing to reduce the attack surface until patching is complete.
## Detection
- **Indicators of Compromise:** Review application logs for unexpected `403` or `500` errors originating from unknown IP addresses targeting `/rest/api/` endpoints.
- **Detection methods and tools:** Utilize the Atlassian "Security Scanner" available in the administration console of most Data Center products to verify patch levels and identify known vulnerabilities.
## References
- **Vendor Advisory:** hxxps[://]confluence[.]atlassian[.]com/security/security-bulletin-march-17-2026-1721271371[.]html
- **Full Portal:** hxxps[://]www[.]atlassian[.]com/trust/security/advisories
- **Cyber Centre Bulletin:** hxxps[://]www[.]cyber[.]gc[.]ca/en/alerts-advisories/atlassian-security-advisory-av26-251