Auth bypass in Testlinkopensourcetrms Testlink
CVE-2026-70561
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.
Vulnerability class: IDOR (Insecure Direct Object Reference)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.004 (31.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 31st percentile — 31.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Testlinkopensourcetrms Testlink — versions 0
Weakness classification (CWE)
References
- github.com/geo-chen/oss/blob/main/testlink-code.md (technical-description)
- github.com/TestLinkOpenSourceTRMS/testlink-code (product)
- www.vulncheck.com/advisories/testlink-and-prior-authenticated-idor-via-attachme… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-70561?
- CVE-2026-70561 is a medium-severity vulnerability in Testlinkopensourcetrms Testlink, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 6.5/10. Published 2026-08-07.
- How severe is CVE-2026-70561?
- Medium severity. CVSS v3 base score is 6.5 out of 10.