The Github repository importer in Atlassian Bitbucket Server before version 5.3.0 allows remote attackers to determine if a service they could not otherwise reach has open ports via a Server Side Request Forgery (SSRF) vulnerability.
The git repository tag rest resource in Atlassian Bitbucket Server from version 3.7.0 before 4.14.11 (the fixed version for 4.14.x), from version 5.0.0 before 5.0.9 (the fixed version for 5.0.x), from version 5.1.0 before 5.1.8 (the fixed version for 5.1.x), from version 5.2.0 before 5.2.6 (the fixed version for 5.2.x), from version 5.3.0 before 5.3.4 (the fixed version for 5.3.x), from version 5.4.0 before 5.4.2 (the fixed version for 5.4.x), from version 5.5.0 before 5.5.1 (the fixed version for 5.5.x) and before 5.6.0 allows remote attackers to read arbitrary files via a path traversal vulnerability through the name of a git tag.
The repository settings resource in Atlassian Bitbucket Server before version 5.6.0 allows remote attackers to read the first line of arbitrary files via a path traversal vulnerability through the default branch name.