CVE-2026-86540 PUBLISHED

knowns before 0.30.0 Arbitrary Code Execution via LSP Binary

Assigner: VulnCheck
Reserved: 07.09.2026 Published: 07.09.2026 Updated: 07.09.2026

knowns versions before 0.30.0 fail to validate the settings.lsp.languages binary field in project configuration files, allowing attackers to execute arbitrary binaries by crafting a malicious .knowns/config.json file. When a repository with a crafted configuration is opened, the unvalidated binary path is executed twice under the user's account without any verification.

CVSS Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CVSS Score: 8.5

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Local	Confidentiality	High	Confidentiality	None
Attack Complexity	Low	Integrity	High	Integrity	None
Attack Requirements	None	Availability	High	Availability	None
Privileges Required	None
User Interaction	Passive

CVSS 4.0

CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS Score: 7.8

Attack Vector	Local	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	High
Privileges Required	None	Integrity Impact	High
User Interaction	Required	Availability Impact	High

CVSS 3.1

Product Status

Vendor	knowns-dev
Product	knowns
Versions	Default: unaffected affected from 0 to 0.30.0 (excl.) Version 0.30.0 is unaffected

Credits

Tong Hoang Gia reporter
Nguyen Huy Hoang reporter

References

Problem Types

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') CWE