What is CVE-2026-7301?

CVE-2026-7301 is a critical-severity vulnerability in Lmsys Sglang, classified under Deserialization of Untrusted Data. CVSS score: 9.8/10. Published 2026-05-18.

How severe is CVE-2026-7301?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Deserialization in Lmsys Sglang

CVE-2026-7301

SGLangs multimodal generation runtime scheduler's ROUTER socket binds to 0.0.0.0 by default and contains a sink that calls pickle.loads() on incoming messages, enabling RCE when exposed to the internet.

Vulnerability class: Insecure Deserialization

Published 2026-05-18 · last modified 2026-10-14.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.004 (34.1th percentile), scored 2026-10-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 34th percentile — 34.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.004 · change: -0.002

Affected products

Lmsys Sglang — versions 0.5.10
Sglang — versions 5.10

Weakness classification (CWE)

CWE-502 — Deserialization of Untrusted Data

References

github.com/sgl-project/sglang/tree/main/python/sglang (Product)
antiproof.ai/blog/three-rces-in-sglang/ (Permissions Required)

Frequently asked questions

What is CVE-2026-7301?: CVE-2026-7301 is a critical-severity vulnerability in Lmsys Sglang, classified under Deserialization of Untrusted Data. CVSS score: 9.8/10. Published 2026-05-18.
How severe is CVE-2026-7301?: Critical severity. CVSS v3 base score is 9.8 out of 10.