CVE-2026-86540

high

Description

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.

References

https://www.vulncheck.com/advisories/knowns-before-0.30.0-arbitrary-code-execution-via-lsp-binary

https://github.com/knowns-dev/knowns/security/advisories/GHSA-mc52-mwq4-vfx3

https://github.com/knowns-dev/knowns/releases/tag/v0.30.0

https://github.com/knowns-dev/knowns/commit/d3989829fb5095666d23d005b2f78a082832a396

https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/models/config.go#L205-L216

https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/lsp/detect.go#L128-L157

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-72558

Details

Source: Mitre, NVD

Published: 2026-09-07

Updated: 2026-09-08

Risk Information

CVSS v2

Base Score: 7.2

Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C

Severity: High

CVSS v3

Base Score: 7.8

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

Severity: High

CVSS v4

Base Score: 8.5

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

Severity: High

EPSS

EPSS: 0.00212