CVE-2026-86540

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 v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/lsp/detect.go#L128-L157
https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/models/config.go#L205-L216
https://github.com/knowns-dev/knowns/commit/d3989829fb5095666d23d005b2f78a082832a396
https://github.com/knowns-dev/knowns/releases/tag/v0.30.0
https://github.com/knowns-dev/knowns/security/advisories/GHSA-mc52-mwq4-vfx3
https://www.vulncheck.com/advisories/knowns-before-0.30.0-arbitrary-code-execution-via-lsp-binary

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-07 23:16

Updated : 2026-09-08 19:56

NVD link : CVE-2026-86540

Mitre link : CVE-2026-86540

CVE.ORG link : CVE-2026-86540

JSON object : View

Products Affected

No product.

CWE

CWE-78

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

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