by Kastro
Paper/Archive/CVE-2026-93839

CVE-2026-93839

ModelTC LightLLM — LightLLM through 1.2.0 Missing Authentication in PD Master /pd_register WebSocket Endpoint

EPSS 0.8%public exploitCVSS 9.8
critical.is priorityof 100
51
CVSS 9.8 (CNA)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 55.3.553 × 2011.1Exploit: SSVC poc+1010.0SSVC exploitation: poc+100.0
Description · from the CVE record

LightLLM through 1.2.0 contains an authentication bypass vulnerability in the /pd_register WebSocket endpoint that allows unauthenticated attackers to register arbitrary nodes by supplying crafted JSON without peer address validation. Attackers can disclose full user prompts routed to their socket, trigger denial of service by replacing legitimate nodes, or make the PD Master issue requests to internal network addresses.

Affected

ProductAffectedFixed inSource
LightLLM≤ 1.2.0–CNA

Scores by source

VulnCheck (CNA)9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
VulnCheck (CNA)9.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CISA ADPSSVCExploitation: poc · Automatable: yes · Technical impact: total

References

exploitgithub.com/ModelTC/LightLLM/issues/1576refgithub.com/ModelTC/LightLLMwriteupgithub.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/api_http_pd.py#L26-L36writeupgithub.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/httpserver_for_pd_master/manager.py#L714-L749writeupgithub.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/httpserver_for_pd_master/manager.py#L691-L698writeupgithub.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/api_http.py#L198-L205writeupvulncheck.com/advisories/lightllm-through-1.2.0-missing-authentication-in-pd-master-pd-register-websocket-endpoint