High severity · published Sep 9, 2026
CVE-2026-86775
knowns before 0.30.0 Path Traversal via Document API
8.6
CVSS
0.7%
EPSS
No
On KEV
Description
knowns (npm package) versions <= 0.29.1 contain a path traversal vulnerability in the Document API. The HTTP handler in internal/server/routes/docs.go normalizes the user-supplied document path with cleanDocPath(), which strips leading/trailing slashes and the .md suffix but does not neutralize ../ traversal sequences, and internal/storage/doc_store.go then builds the target path with filepath.Join(ds.docsDir(), filepath.FromSlash(doc.Path)+".md") without verifying that the resolved path remains inside the documents directory. In the default deployment, where the Management API is unauthenticated and bound to all interfaces, a remote unauthenticated attacker can supply a traversal payload (for example {"path": "../../../../tmp/knowns_pwn_marker"} to POST /api/docs, or an encoded path to GET /api/docs/...) to read, create, overwrite, or delete arbitrary files with a .md extension anywhere on the host filesystem and to create arbitrary directories via os.MkdirAll. This can expose sensitive data stored in other projects' documentation, corrupt or destroy files, and provide an arbitrary-write primitive that may be chained toward code execution. The issue is fixed in version 0.30.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
High
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 55% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KN
knowns · knowns-dev
before 0.30.0 · source: vendor
Affected product
KN
knowns
knowns-dev
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