TestLink through 1.9.20 allows type juggling for authentication bypass because === is not used.

Multiple SQL injection vulnerabilities in TestLink through 1.9.19 allows remote authenticated users to execute arbitrary SQL commands via the (1) tproject_id parameter to keywordsView.php; the (2) req_spec_id parameter to reqSpecCompareRevisions.php; the (3) requirement_id parameter to reqCompareVersions.php; the (4) build_id parameter to planUpdateTC.php; the (5) tplan_id parameter to newest_tcversions.php; the (6) tplan_id parameter to tcCreatedPerUserGUI.php; the (7) tcase_id parameter to tcAssign2Tplan.php; or the (8) testcase_id parameter to tcCompareVersions.php. Authentication is often easy to achieve: a guest account, that can execute this attack, can be created by anyone in the default configuration.

TestLink before 1.9.20 allows XSS via non-lowercase javascript: in the index.php reqURI parameter. NOTE: this issue exists because of an incomplete fix for CVE-2019-19491.

TestLink through 1.9.16 allows remote attackers to read arbitrary attachments via a modified ID field to /lib/attachments/attachmentdownload.php.

Multiple cross-site scripting (XSS) vulnerabilities in TestLink before 1.9.14 allow remote attackers to inject arbitrary web script or HTML via the (1) selected_end_date or (2) selected_start_date parameter to lib/results/tcCreatedPerUserOnTestProject.php; the (3) containerType parameter to lib/testcases/containerEdit.php; the (4) filter_tc_id or (5) filter_testcase_name parameter to lib/testcases/listTestCases.php; the (6) useRecursion parameter to lib/testcases/tcImport.php; the (7) targetTestCase or (8) created_by parameter to lib/testcases/tcSearch.php; or the (9) HTTP Referer header to third_party/user_contribution/fakeRemoteExecServer/client4fakeXMLRPCTestRunner.php.

SQL injection vulnerability in TestLink before 1.9.14 allows remote attackers to execute arbitrary SQL commands via the apikey parameter to lnl.php.

lib/functions/database.class.php in TestLink before 1.9.13 allows remote attackers to obtain sensitive information via unspecified vectors, which reveals the installation path in an error message.

lib/execute/execSetResults.php in TestLink before 1.9.13 allows remote attackers to conduct PHP object injection attacks and execute arbitrary PHP code via the filter_result_result parameter.