CVE-2026-86541CWE-22path-traversal

CVE-2026-86541

High · published September 8, 2026

CVSS v3.1
8.3
EPSS
1%
Percentile
55.2
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
8.3 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:H
CVSS v4.0
7.2 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:H/VA:H/SC:N/SI:N/SA:N
EPSS
0.00768 · 55.2th percentile
Weakness
CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Published
2026-09-08T03:16Z
References (5)
https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/mcp/handlers/code.go#L588-L646 · [email protected]https://github.com/knowns-dev/knowns/commit/a2c98fc5c313463576c9348beeec6a74ddd7333b · [email protected]https://github.com/knowns-dev/knowns/releases/tag/v0.30.0 · [email protected]https://github.com/knowns-dev/knowns/security/advisories/GHSA-f539-xgc6-xw7q · [email protected]https://www.vulncheck.com/advisories/knowns-before-0.30.0-path-traversal-via-code-replace-mcp-action · [email protected]
EPSS history
Timeline
  • 09 SEP 03:20Z
    EPSS moved — → 1%
    epss
  • 07 SEP 23:03Z
    knowns before 0.30.0 Path Traversal via code.replace MCP action
    cvelistv5