{"id":"CVE-2026-41399","aliases":["EUVD-2026-26107","GHSA-f44p-c7w9-7xr7"],"status":"published","title":"OpenClaw \u003c 2026.3.28 - Denial of Service via Unbounded Pre-auth WebSocket Upgrades","description":"OpenClaw before 2026.3.28 accepts unbounded concurrent unauthenticated WebSocket upgrades without pre-authentication budget allocation. Unauthenticated network attackers can exhaust socket and worker capacity to disrupt WebSocket availability for legitimate clients.","severity":{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-08","score":0.00318,"percentile":0.24914,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-400","CWE-770"],"published":"2026-03-31T23:54:00Z","modified":"2026-10-28T02:31:00Z","fixes":[{"ecosystem":"npm","package":"openclaw","fixed_in":["2026.3.28"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"openclaw","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"2026.3.24"},{"fixed":"2026.3.28"}]}]},{"source":"osv","ecosystem":"npm","package":"openclaw","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"2026.3.28"}]}]}],"products":[{"vendor":"openclaw","product":"openclaw"}],"references":[{"url":"https://github.com/openclaw/openclaw/security/advisories/GHSA-f44p-c7w9-7xr7","tags":["vendor-advisory","Patch","Vendor Advisory","advisory","web"]},{"url":"https://www.vulncheck.com/advisories/openclaw-denial-of-service-via-unbounded-pre-auth-websocket-upgrades","tags":["third-party-advisory","Third Party Advisory","advisory"]},{"url":"https://github.com/openclaw/openclaw/commit/cb5f7e201f3f86ad70e199ef850e636b4cc457ba","tags":["web"]},{"url":"https://github.com/advisories/GHSA-f44p-c7w9-7xr7"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/41xxx/CVE-2026-41399.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-41399","tags":["advisory"]},{"url":"https://github.com/openclaw/openclaw","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-41399","title":"OpenClaw \u003c 2026.3.28 - Denial of Service via Unbounded Pre-auth WebSocket Upgrades","description":"OpenClaw before 2026.3.28 accepts unbounded concurrent unauthenticated WebSocket upgrades without pre-authentication budget allocation. Unauthenticated network attackers can exhaust socket and worker capacity to disrupt WebSocket availability for legitimate clients.","status":"published","published":"2026-04-28T18:09:57.805Z","modified":"2026-04-29T12:51:43.432Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T13:41:08.498858Z"}],"euvd":[{"id":"EUVD-2026-26107","description":"OpenClaw before 2026.3.28 accepts unbounded concurrent unauthenticated WebSocket upgrades without pre-authentication budget allocation. Unauthenticated network attackers can exhaust socket and worker capacity to disrupt WebSocket availability for legitimate clients.","status":"published","published":"2026-04-28T18:09:57Z","modified":"2026-04-29T12:51:43Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T19:05:19.922616Z"}],"ghsa":[{"id":"GHSA-f44p-c7w9-7xr7","title":"OpenClaw: Gateway WebSocket Denial of Service via unbounded pre-auth upgrades","description":"## Summary\n\nThe gateway accepted unbounded concurrent unauthenticated WebSocket upgrades before allocating them to an authenticated session budget.\n\n## Impact\n\nAn unauthenticated network attacker could consume socket and worker capacity and disrupt WebSocket availability for legitimate clients.\n\n## Affected Component\n\n`src/gateway/server-http.ts, src/gateway/server/preauth-connection-budget.ts`\n\n## Fixed Versions\n\n- Affected: `\u003c= 2026.3.24`\n- Patched: `\u003e= 2026.3.28`\n- Latest stable `2026.3.28` contains the fix.\n\n## Fix\n\nFixed by commit `cb5f7e201f` (`gateway: cap concurrent pre-auth websocket upgrades`).\n\nDiscovered by：Topsec AlphaLab (wang dong)","status":"published","published":"2026-03-31T23:54:00Z","modified":"2026-04-28T18:22:28Z","cvss":[{"version":"4.0","score":5.3,"vector":"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","level":"medium"}],"cwes":["CWE-400","CWE-770"],"updated_at":"2026-11-02T14:39:59.776263Z"}],"nvd":[{"id":"CVE-2026-41399","description":"OpenClaw before 2026.3.28 accepts unbounded concurrent unauthenticated WebSocket upgrades without pre-authentication budget allocation. Unauthenticated network attackers can exhaust socket and worker capacity to disrupt WebSocket availability for legitimate clients.","status":"published","published":"2026-04-28T19:37:43.42Z","modified":"2026-06-17T10:46:39.683Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:12:16.252509Z"}],"osv":[{"id":"CVE-2026-41399","title":"OpenClaw \u003c 2026.3.28 - Denial of Service via Unbounded Pre-auth WebSocket Upgrades","description":"OpenClaw before 2026.3.28 accepts unbounded concurrent unauthenticated WebSocket upgrades without pre-authentication budget allocation. Unauthenticated network attackers can exhaust socket and worker capacity to disrupt WebSocket availability for legitimate clients.","status":"published","published":"2026-04-28T18:09:57.805Z","modified":"2026-10-28T02:31:00.631502307Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T15:45:03.764807Z"},{"id":"GHSA-f44p-c7w9-7xr7","title":"OpenClaw: Gateway WebSocket Denial of Service via unbounded pre-auth upgrades","description":"## Summary\n\nThe gateway accepted unbounded concurrent unauthenticated WebSocket upgrades before allocating them to an authenticated session budget.\n\n## Impact\n\nAn unauthenticated network attacker could consume socket and worker capacity and disrupt WebSocket availability for legitimate clients.\n\n## Affected Component\n\n`src/gateway/server-http.ts, src/gateway/server/preauth-connection-budget.ts`\n\n## Fixed Versions\n\n- Affected: `\u003c= 2026.3.24`\n- Patched: `\u003e= 2026.3.28`\n- Latest stable `2026.3.28` contains the fix.\n\n## Fix\n\nFixed by commit `cb5f7e201f` (`gateway: cap concurrent pre-auth websocket upgrades`).\n\nDiscovered by：Topsec AlphaLab (wang dong)","status":"published","published":"2026-03-31T23:54:00Z","modified":"2026-05-05T16:11:44.936766Z","cvss":[{"version":"4.0","score":5.3,"vector":"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","level":"medium"}],"cwes":["CWE-400","CWE-770"],"updated_at":"2026-11-02T15:46:45.639885Z"}]}}