CVE-2021-47760Public exploitNetwork attack vector

Unauthenticated attachment disclosure via skipCheck bypass

Published Jan 15, 2026 · Updated Jan 15, 2026

Authorization bypass in TestLink 1.16 through 1.19 allows remote attackers to download stored attachments without authentication. The attachmentdownload.php handler trusts the id query value and honors skipCheck=1, suppressing the access check before returning the selected file. No credentials or user interaction are required; however, the CVE record is rejected as a duplicate of unrelated CVE-2021-42220.

CVSS severityUnavailable
Unscored
EPSS probabilityUnavailable
No score available in this record
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authorization bypass in TestLink 1.16 through 1.19 allows remote attackers to download stored attachments without authentication. The attachmentdownload.php handler trusts the id query value and honors skipCheck=1, suppressing the access check before returning the selected file. No credentials or user interaction are required; however, the CVE record is rejected as a duplicate of unrelated CVE-2021-42220.

The record

CVE
CVE-2021-47760
Published
Jan 15, 2026
Updated
Jan 15, 2026
Vendor
TestLink Development Team
Product
TestLink
Classifications
T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.16 <= 1.19

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

TestLink Development Team · TestLinkversion=1.16 <= 1.19

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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