CVE-2026-93839 json
LightLLM through 1.2.0 Missing Authentication in PD Master /pd_register WebSocket Endpoint
published last mo. modified last mo. also EUVD-2026-83283
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.8%
- EPSS 0.8% chance of exploitation in 30 days, percentile 55%
- public exploits
- 0
- none known
Summary
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.
Is CVE-2026-93839 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- total
- Assessed
- last mo.
Exploit prediction
0.76% chance of exploitation in the next 30 days, higher than 55% of all scored CVEs (FIRST EPSS, 2026-11-11).
Exploits and checks
- github.com https://github.com/ModelTC/LightLLM/issues/1576 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 9.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| CNA | 4.0 | 9.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/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 |
Affected products
- ModelTC LightLLM
Classification
- Weakness
-
- CWE-306 Missing Authentication for Critical Functionality
References
-
github.com
/ModelTC/LightLLM/issues/1576
issue-tracking, exploit
-
github.com
/ModelTC/LightLLM
product
-
github.com
/ModelTC/lightllm/blob/v1.2.0/lightllm/server/api_http_pd.py#L26-L36
technical-description
-
github.com
/ModelTC/lightllm/blob/v1.2.0/lightllm/server/httpserver_for_pd_master/manager.py#L714-L749
technical-description
-
github.com
/ModelTC/lightllm/blob/v1.2.0/lightllm/server/httpserver_for_pd_master/manager.py#L691-L698
technical-description
-
github.com
/ModelTC/lightllm/blob/v1.2.0/lightllm/server/api_http.py#L198-L205
technical-description
-
vulncheck.com
/advisories/lightllm-through-1.2.0-missing-authentication-in-pd-master-pd-register-websocket-endpoint
third-party-advisory
Sources
- CVE List CVE-2026-93839
- NVD CVE-2026-93839
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.