8.8
HIGH CVSS 4.0
CVE-2026-86775
knowns before 0.30.0 Path Traversal via Document API
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.

INFO

Published Date :

Sept. 9, 2026, 2:17 p.m.

Last Modified :

Sept. 9, 2026, 2:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-86775 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 HIGH [email protected]
CVSS 4.0 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 HIGH [email protected]
Solution
Update the knowns package to version 0.30.0 or later to fix path traversal.
  • Update knowns package to version 0.30.0.
  • Verify no user-supplied paths are accepted.
  • Ensure paths are validated before use.
  • Restrict API access to authenticated users.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-86775.

URL Resource
https://github.com/knowns-dev/knowns/security/advisories/GHSA-3h35-4jq7-hv45
https://www.vulncheck.com/advisories/knowns-before-0.30.0-path-traversal-via-document-api
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-86775 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-86775 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-86775 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Sep. 09, 2026

    Action Type Old Value New Value
    Added 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.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L
    Added CWE CWE-22
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/86xxx/CVE-2026-86775.json">CVE-2026-86775</a>
    Added Reference https://github.com/knowns-dev/knowns/security/advisories/GHSA-3h35-4jq7-hv45
    Added Reference https://www.vulncheck.com/advisories/knowns-before-0.30.0-path-traversal-via-document-api
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.