TestLink 1.9.20 and prior contains an insecure direct object reference vulnerability that allows any authenticated user, including low-privilege guest accounts, to read arbitrary attachments by supplying an integer attachment ID to the attachmentdownload.php handler without any project or role authorization check. Attackers can enumerate sequential integer IDs through the attachment download endpoint to retrieve file contents from private projects they have no membership in, bypassing the per-project access control model and exposing test specifications, requirements documents, execution evidence, and other sensitive uploaded files across the entire installation.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
None
No data modification
Availability
None
No disruption
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products
testlinkopensourcetrms:testlink