Vulnerability · Published Sep 7, 2026 · Assigned by VulnCheck

CVE-2026-86541knowns before 0.30.0 Path Traversal via code.replace MCP action

High 8.3

In plain English

A high-severity path traversal in knowns from knowns-dev. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.8% (higher than 56% of all known vulnerabilities).

Severity (CVSS 3.1)8.3High

Exploit odds (30 days)0.8%top 44.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

knowns versions before 0.30.0 contain a path traversal vulnerability in the handleCodeReplace() function that allows attackers to overwrite arbitrary files outside the project root. Attackers can supply absolute paths or relative paths containing directory traversal sequences to write malicious content to sensitive files like shell startup scripts or SSH configuration files.

Affected products (as reported)

Vendor	Product	Versions
knowns-dev	knowns	0 – before 0.30.0

Weakness: CWE-22 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:H

References

GitHub Security Advisory (GHSA-f539-xgc6-xw7q) vendor-advisory
handleCodeReplace resolves and writes the caller-supplied path without containment (v0.29.1) technical-description
knowns fix commit a2c98fc5c313 patch
knowns v0.30.0 Release Notes release-notes
VulnCheck Advisory: knowns before 0.30.0 Path Traversal via code.replace MCP action third-party-advisory