CVE-2026-103042 — LightLLM through 1.2.0 Unauthenticated Memory Exhaustion via NCCL Control Channel set_value
LightLLM through 1.2.0 contains a memory exhaustion vulnerability in the NCCL control channel when started with --pd_trans_mode nccl, allowing unauthenticated attackers to exhaust KV-transfer worker memory. Attackers can call the exposed_set_value method to store unbounded key-value pairs without size limits, causing the worker process to crash and triggering node failure.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.5% (30-day exploitation probability)+6
- Technical severity (high)+6
- CISA SSVC: exploitation "poc"+5
- Automatable exploitation (SSVC)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (ModelTC LightLLM).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes matching the vulnerability class (denial of service), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 8.7 | CVSS 4.0 | High | — | — | disclosure@vulncheck.com via NIST National Vulnerability Database |
| 8.7 | CVSS 4.0 | High | — | — | VulnCheck via CVE Program (cve.org) e CISA ADP |
| 7.5 | CVSS 3.1 | High | 3.9 | 3.6 | disclosure@vulncheck.com via NIST National Vulnerability Database |
| 7.5 | CVSS 3.1 | High | — | — | VulnCheck via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (score shown at the top: disclosure@vulncheck.com) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
CWE-770 · Allocation of Resources Without Limits or Throttling
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Track CPU/memory spikes and availability drops correlated with request patterns.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · modeltc/lightllm
- SSVC assessment updated
- Record published
- CVSS changed · 7.5
- Source status changed · → Deferred
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
6 on the record
- github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/router/model_infer/mode_
- github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/router/model_infer/mode_
- github.com/ModelTC/LightLLM
- www.vulncheck.com/advisories/lightllm-through-1.2.0-unauthenticated-memory-exhaustion-v
- github.com/ModelTC/LightLLM/issues/1595
- github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/router/model_infer/mode_
Elsewhere on this site
Related CVEs (same products)
- High CVE-2026-111160 LightLLM through 1.2.0 Unauthenticated DoS via pd_kv_trans_params Deserialization 10h
- Critical CVE-2026-103395 LightLLM through 1.2.0 Unauthenticated Remote Code Execution via Visual-Only RPyC Service 15d
- Medium CVE-2026-103243 LightLLM through 1.2.0 Server-Side Request Forgery via multimodal endpoints 15d
- High CVE-2026-103270 LightLLM through 1.2.0 Missing Authentication on RL Control Routes 15d
- Critical CVE-2026-103040 LightLLM through 1.2.0 Unauthenticated Remote Code Execution via Router Profiler RPyC Service 16d
- Critical CVE-2026-103041 LightLLM through 1.2.0 Unauthenticated Remote Code Execution via Embed Cache RPyC Service 16d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No fixed version, patch or mitigation documented.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-103042 is "LightLLM through 1.2.0 Unauthenticated Memory Exhaustion via NCCL Control Channel set_value", rated High. It affects LightLLM (ModelTC); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.5 describes technical severity. EPSS 0.52% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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