Description
OpenClaw versions prior to 2026.2.21 sandbox browser entrypoint launches x11vnc without authentication for noVNC observer sessions, allowing unauthenticated access to the VNC interface. Remote attackers on the host loopback interface can connect to the exposed noVNC port to observe or interact with the sandbox browser without credentials.
Affected products
openclaw: openclaw
References4
- github.com/openclaw/openclaw/security/advisories/GHSA-25gx-x37c… MitigationVendor Advisory
- github.com/openclaw/openclaw/commit/621d8e1312482f122f18c43c72c… Patch
- github.com/openclaw/openclaw/commit/8c1518f0f3e0533593cd2dec3a4… Patch
- www.vulncheck.com/advisories/openclaw-missing-vnc-authenticatio… Third Party Advisory
Metrics
- CVSS 3.1
-
9.1
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - CVSS 4.0
-
8.5
HIGH
Score source: CNA
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 1% percentile: 46 · as of 12 November 2026
- CWE
- CWE-306
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.