An privilege escalation issue was discovered in Gitlab versions < 12.1.2, < 12.0.4, and < 11.11.6 when Mattermost slash commands are used with a blocked account.

An access control issue exists in < 12.3.5, < 12.2.8, and < 12.1.14 for GitLab Community Edition (CE) and Enterprise Edition (EE) where private merge requests and issues would be disclosed with the Group Search feature provided by Elasticsearch integration

A XSS exists in Gitlab CE/EE < 12.1.10 in the Mermaid plugin.

Improper authentication exists in < 12.3.2, < 12.2.6, and < 12.1.12 for GitLab Community Edition (CE) and Enterprise Edition (EE) in the GitLab SAML integration had a validation issue that permitted an attacker to takeover another user's account.

An information disclosure exists in < 12.3.2, < 12.2.6, and < 12.1.12 for GitLab Community Edition (CE) and Enterprise Edition (EE). When an issue was moved to a public project from a private one, the associated private labels and the private project namespace would be disclosed through the GitLab API.

An IDOR was discovered in < 12.3.2, < 12.2.6, and < 12.1.12 for GitLab Community Edition (CE) and Enterprise Edition (EE) that allowed a maintainer to add any private group to a protected environment.

An IDOR exists in < 12.3.2, < 12.2.6, and < 12.1.12 for GitLab Community Edition (CE) and Enterprise Edition (EE) that allowed a project owner or maintainer to see the members of any private group via merge request approval rules.

An information disclosure exists in < 12.3.2, < 12.2.6, and < 12.1.12 for GitLab Community Edition (CE) and Enterprise Edition (EE) where the assignee(s) of a confidential issue in a private project would be disclosed to a guest via milestones.

An information disclosure exists in < 12.3.2, < 12.2.6, and < 12.1.12 for GitLab Community Edition (CE) and Enterprise Edition (EE). The path of a private project, that used to be public, would be disclosed in the unsubscribe email link of issues and merge requests.

An issue was discovered in GitLab Community Edition (CE) and Enterprise Edition (EE) 10.8 through 12.6.1. It has Incorrect Access Control.

An issue was discovered in GitLab Enterprise Edition (EE) 8.9.0 through 12.6.1. Using the project import feature, it was possible for someone to obtain issues from private projects.

An issue was discovered in GitLab Community Edition (CE) and Enterprise Edition (EE) 5.1 through 12.6.1. It has Incorrect Access Control.

An issue was discovered in GitLab Community Edition (CE) and Enterprise Edition (EE) 8.13 through 12.6.1. It has Incorrect Access Control.

An issue was discovered in GitLab Community Edition (CE) and Enterprise Edition (EE) 9.1 through 12.6.1. It has Incorrect Access Control.

An issue was discovered in GitLab Community Edition (CE) and Enterprise Edition (EE) 11.0 through 12.6. It allows Uncontrolled Resource Consumption.

An issue was discovered in GitLab Community Edition (CE) and Enterprise Edition (EE) 11.4 through 12.6.1. It has Incorrect Access Control.

In GitLab EE 10.5 through 12.5.3, 12.4.5, and 12.3.8, when transferring a public project to a private group, private code would be disclosed via the Group Search API provided by the Elasticsearch integration.

In GitLab EE 11.3 through 12.5.3, 12.4.5, and 12.3.8, insufficient parameter sanitization for the Maven package registry could lead to privilege escalation and remote code execution vulnerabilities under certain conditions.

GitLab EE 8.4 through 12.5, 12.4.3, and 12.3.6 stored several tokens in plaintext.

GitLab EE 8.14 through 12.5, 12.4.3, and 12.3.6 has Incorrect Access Control. After a project changed to private, previously forked repositories were still able to get information about the private project through the API.