---
title: "CVE-2026-93839: LightLLM - Authentication Bypass"
description: "LightLLM through 1.2.0 contains an authentication bypass caused by lack of peer address validation in /pd_register WebSocket endpoint, letting unauthenticated attackers register arbitrary nodes and cause information disclosure and denial of service."
url: https://panop.io/threat-heartbeat/CVE-2026-93839/
---

# CVE-2026-93839 LightLLM - Authentication Bypass

LightLLM through 1.2.0 contains an authentication bypass caused by lack of peer address validation in /pd\_register WebSocket endpoint, letting unauthenticated attackers register arbitrary nodes and cause information disclosure and denial of service.

CVSS base score 9.8 /10

Critical

CISA KEV

Not listed

Public exploit

None known

Authentication

Not required

EPSS

0.76% chance of exploitation in 30 days

[View the NVD record ↗](https://nvd.nist.gov/vuln/detail/CVE-2026-93839)

## Details

Type

Authentication Bypass

Impact

Information Disclosure, Denial Of Service

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Published

18 September 2026

Updated

15 October 2026

Weakness

[CWE-306](https://cwe.mitre.org/data/definitions/306.html)

## Vendor fix

Update to the latest version beyond 1.2.0.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

## References

- [https://nvd.nist.gov/vuln/detail/CVE-2026-93839](https://nvd.nist.gov/vuln/detail/CVE-2026-93839)
- [https://github.com/ModelTC/LightLLM](https://github.com/ModelTC/LightLLM)
- [https://github.com/ModelTC/LightLLM/issues/1576](https://github.com/ModelTC/LightLLM/issues/1576)
- [https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/api\_http.py#L198-L205](https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/api_http.py#L198-L205)
- [https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/api\_http\_pd.py#L26-L36](https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/api_http_pd.py#L26-L36)
- [https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/httpserver\_for\_pd\_master/manager.py#L691-L698](https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/httpserver_for_pd_master/manager.py#L691-L698)
- [https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/httpserver\_for\_pd\_master/manager.py#L714-L749](https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/httpserver_for_pd_master/manager.py#L714-L749)
- [https://www.vulncheck.com/advisories/lightllm-through-1.2.0-missing-authentication-in-pd-master-pd-register-websocket-endpoint](https://www.vulncheck.com/advisories/lightllm-through-1.2.0-missing-authentication-in-pd-master-pd-register-websocket-endpoint)

[← All CVEs](https://panop.io/threat-heartbeat/)

## What this record can't tell you

- Whether you run the affected software, and where
- Whether an attacker can actually reach and exploit it
- The misconfigurations that never get a CVE number
- What it would cost the business, ranked into what to fix first

Panop answers these inside your environment, for this CVE and every other finding.

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