CVE-2026-41399
OpenClaw: Gateway WebSocket Denial of Service via unbounded pre-auth upgrades
Description
## Summary The gateway accepted unbounded concurrent unauthenticated WebSocket upgrades before allocating them to an authenticated session budget. ## Impact An unauthenticated network attacker could consume socket and worker capacity and disrupt WebSocket availability for legitimate clients. ## Affected Component `src/gateway/server-http.ts, src/gateway/server/preauth-connection-budget.ts` ## Fixed Versions - Affected: `<= 2026.3.24` - Patched: `>= 2026.3.28` - Latest stable `2026.3.28` contains the fix. ## Fix Fixed by commit `cb5f7e201f` (`gateway: cap concurrent pre-auth websocket upgrades`). Discovered by：Topsec AlphaLab (wang dong)
How to fix CVE-2026-41399
To remediate CVE-2026-41399, upgrade the affected package to a fixed version below.
- —upgrade to 2026.3.28 or later
Is CVE-2026-41399 being exploited?
Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 2026.3.28
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N |