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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.14%). 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 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 4.0
- 8.5 HIGHCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/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
- 0.14% probability · 4th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-78
- Source
- disclosure@vulncheck.com
References
- 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
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.