CVE-2026-7301: SGLang RCE via insecure pickle deserialization in scheduler ROUTER socket

CVE-2026-7301 · Severity: critical · CVSS 9.8 · Published 2026-05-18

SGLang, an open-source framework for serving large language AI models, contains a critical security flaw in its multimodal generation component. The software's internal communication system is exposed to the network by default and processes incoming data insecurely. An attacker can exploit this to gain full control over the server running the AI model, potentially leading to data theft, service disruption, or unauthorized access to corporate infrastructure.

Technologies: sglang (PyPI), SGLang Project SGLang. Vendors: PyPI, SGLang Project.

Quick answers

Is CVE-2026-7301 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-7301 being exploited in the wild.
How severe is CVE-2026-7301?
Critical severity, with a CVSS score of 9.8, published 18 May 2026.
Which products and versions are affected?
sglang (PyPI) ECOSYSTEM:introduced=0.5.5,last_affected=0.5.12; SGLang Project SGLang >= 0.5.5, <= 0.5.12, 0.5.5 and later.
Is there a fix for CVE-2026-7301?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-7301 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-7301?
Check whether you run sglang (PyPI) or SGLang Project SGLang at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A deserialization vulnerability (CWE-502) exists in the SGLang multimodal generation runtime scheduler. The scheduler utilizes a ZeroMQ ROUTER socket that, while defaulting to localhost in code, is frequently bound to 0.0.0.0 in official deployment configurations (Docker, SkyPilot, AWS SageMaker). The 'scheduler.py' component invokes 'pickle.loads()' on the payload of incoming multipart messages without prior validation. An unauthenticated remote attacker can send a crafted Python pickle object to the exposed port to achieve arbitrary code execution with the privileges of the SGLang process. As of the advisory date, no official patch is available; users are advised to restrict network access to SGLang interfaces.

Affected products

  • SGLang Project sglang >= 0.5.5, <= 0.5.12

Identifiers

  • CVE-2026-7301
  • GHSA-gwv6-pq6m-p3rq
  • PYSEC-2026-536

Timeline

  • 2026-03-10: disclosed: Responsibly disclosed to SGLang maintainers by Antiproof
  • 2026-05-18: advisory: Published to GitHub Advisory Database and NVD

References

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