CVE-2026-86538

knowns versions before 0.30.0 contain a path traversal vulnerability in the POST /api/templates/preview endpoint that allows unauthenticated attackers to read arbitrary files. Attackers can supply directory traversal sequences in the templateFile parameter to bypass path restrictions and read sensitive files like credentials and configuration through the JSON response.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/server/routes/templates.go#L299-L310
https://github.com/knowns-dev/knowns/commit/09c5a96fd5817b941dc86669278c1a17db10ed4e
https://github.com/knowns-dev/knowns/releases/tag/v0.30.0
https://github.com/knowns-dev/knowns/security/advisories/GHSA-fpxv-c555-rhm3
https://www.vulncheck.com/advisories/knowns-before-0.30.0-path-traversal-via-templatefile-parameter

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-07 23:16

Updated : 2026-09-14 20:17

NVD link : CVE-2026-86538

Mitre link : CVE-2026-86538

CVE.ORG link : CVE-2026-86538

JSON object : View

Products Affected

No product.

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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