CVE-2026-86541
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.53%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 7.2 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:H/VA:H/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/M
- EPSS
- 0.53% probability · 43th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-22
- Source
- disclosure@vulncheck.com
References
- https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/mcp/handlers/code.go#L588-L646
- https://github.com/knowns-dev/knowns/commit/a2c98fc5c313463576c9348beeec6a74ddd7333b
- https://github.com/knowns-dev/knowns/releases/tag/v0.30.0
- https://github.com/knowns-dev/knowns/security/advisories/GHSA-f539-xgc6-xw7q
- https://www.vulncheck.com/advisories/knowns-before-0.30.0-path-traversal-via-code-replace-mcp-action
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.