What is CVE-2026-39866?

CVE-2026-39866 is a high-severity vulnerability in Lawnchair, classified under Command Injection. CVSS score: 8.8/10. Published 2026-04-21.

How severe is CVE-2026-39866?

High severity. CVSS v3 base score is 8.8 out of 10.

Is CVE-2026-39866 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

RCE in Lawnchair

CVE-2026-39866

Lawnchair is a free, open-source home app for Android. Prior to commit fcba413f55dd47f8a3921445252849126c6266b2, command injection in release_update.yml workflow dispatch input allows arbitrary code execution. Commit fcba413f55dd47f8a39214…

Vulnerability class: Command Injection (OS Command Injection)

EPSS: 0.023 (81.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Lawnchair
Lawnchairlauncher Lawnchair — versions < fcba413f55dd47f8a3921445252849126c6266b2

Weakness classification (CWE)

CWE-77 — Command Injection

Public proof-of-concept exploits

abhayclasher/CVE-2026-39866

References

security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)
security-advisories@github.com (Patch, x_refsource_MISC)

Frequently asked questions

What is CVE-2026-39866?: CVE-2026-39866 is a high-severity vulnerability in Lawnchair, classified under Command Injection. CVSS score: 8.8/10. Published 2026-04-21.
How severe is CVE-2026-39866?: High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2026-39866 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.