SGLang exposes two endpoints that allow an unauthenticated, remote attacker to trigger distributed weight broadcasting using NCCL and to initiate data transfer, thereby enabling the exfiltration of all model weights. The vulnerability arises when no API keys are configured, resulting in unrestricted access to these endpoints and the associated weight transfer functionality. The primary impact is the unintended disclosure of confidential model weights, which could compromise proprietary information and intellectual property.

SGLang is affected, and the vulnerability applies to all deployed versions that have the two exposed endpoints active and no API keys configured. No specific version numbers are listed in the advisory.

The CVSS score of 7.5 indicates a high severity vulnerability. The EPSS score is below 1 percent, indicating that exploit attempts are currently uncommon, though the vulnerability is still present and not listed as a known exploited vulnerability in the CISA KEV catalog. The attack vector is likely remote, accessed over a network, where an attacker activates the endpoints to receive the full set of model weights. Because the flaw results in information exposure governed by CWE‑306, it permits an attacker to obtain complete model data without authentication, posing an immediate confidentiality risk.