CVE-2021-26069: 
JIRA vulnerability analysis and mitigation

CVE-2021-26069 is an Information Disclosure vulnerability affecting Atlassian Jira Server and Data Center. The vulnerability was discovered in January 2021 and allows unauthenticated remote attackers to download temporary files and enumerate project keys through the /rest/api/1.0/issues/{id}/ActionsAndOperations API endpoint. The affected versions include releases before version 8.5.11, versions 8.6.0 to 8.13.3 (excluding 8.13.3), and versions 8.14.0 to 8.15.0 (excluding 8.15.0) (Jira Advisory).

The vulnerability exists in the REST API endpoint /rest/api/1.0/issues/{id}/ActionsAndOperations which improperly handles access controls. It received a CVSS v3.1 Base Score of 5.3 (Medium) with the vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N, indicating that it can be exploited remotely without authentication or user interaction, but only results in low-level information disclosure (NVD).

The vulnerability allows unauthorized attackers to access temporary files and enumerate project keys in Jira installations. While the direct impact is limited to information disclosure without system modification capabilities, it could potentially provide attackers with valuable reconnaissance information about the target system (NVD).

Atlassian has released fixed versions to address this vulnerability. Users should upgrade to version 8.5.11 if running a version before 8.5.11, version 8.13.3 if running versions between 8.6.0 and 8.13.3, or version 8.15.0 if running versions between 8.14.0 and 8.15.0 (Jira Advisory).