GitLab has remediated an issue in GitLab CE/EE affecting all versions from 13.7 before 18.9.7, 18.10 before 18.10.6, and 18.11 before 18.11.3 that could have allowed an authenticated user to view Jira issues outside the configured project scope due to an integration filter functioning only as a display control rather than enforcing access boundaries as specified.
Upgrade to versions 18.9.7, 18.10.6, 18.11.3 or above. Additionally, review the Jira API token used in your integration and ensure it is scoped to only the Jira projects you intend to expose. The project keys field in the integration configuration filters the displayed issues but does not restrict the token's access. To limit which issues can be read through the integration, generate the API token from a Jira account with access only to the desired projects.