# CVE-2026-15971: SGLang RCE via eval sandbox escape in dumper subsystem

Source: https://junglewise.ai/threats/cve-2026-15971-sglang-rce-via-eval-sandbox-escape-in-dumper-subsystem  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-30. Updated: 2026-07-30  
License: CC BY 4.0 with a link back

CVE-2026-15971 · Severity: info · CVSS 9.8 · Published 2026-07-30

SGLang, an open-source framework for serving Large Language Models (LLMs), contains a critical security flaw in its optional debugging subsystem. If the 'dumper' feature is enabled, remote attackers can bypass security restrictions to execute arbitrary code on the server hosting the AI model. This could lead to a complete system takeover, theft of proprietary AI models, or unauthorized access to sensitive data processed by the inference engine.

Technologies: [SGLang Project SGLang](https://junglewise.ai/threats/technologies/sglang). Vendors: [SGLang Project](https://junglewise.ai/threats/vendors/sglang-project).

## Quick answers

**Is CVE-2026-15971 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-15971 being exploited in the wild.

**How severe is CVE-2026-15971?** Informational severity, with a CVSS score of 9.8, published 30 July 2026.

**Which products and versions are affected?** SGLang Project SGLang <= v0.5.15.

**Is there a fix for CVE-2026-15971?** 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-2026-15971 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-15971?** Check whether you run 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 remote code execution (RCE) vulnerability exists in SGLang's optional 'dumper' subsystem. The vulnerability is rooted in the use of an unsafe `eval()` call within a debugging component that lacks sufficient sandboxing. When the `DUMPER_SERVER_PORT` environment variable is set, the dumper HTTP control plane becomes active. An attacker can send specially crafted inference requests that trigger the dumper to evaluate malicious Python code, leading to a sandbox escape and execution of arbitrary commands with the privileges of the SGLang process. This is part of a broader architectural issue where administrative and debugging routes may lack enforced authentication if API keys are not explicitly configured.

## Affected products

- SGLang Project SGLang <= v0.5.15

## Timeline

- 2026-04-22: disclosed: Initial disclosure to maintainers via GitHub Security Advisories.
- 2026-07-30: advisory: Public disclosure and CERT/CC coordination.

## References

- [https://github.com/sgl-project/sglang/security/advisories/GHSA-h6rf-77vv-9mvj](https://github.com/sgl-project/sglang/security/advisories/GHSA-h6rf-77vv-9mvj)
- [https://thoughts.apoorvdayal.com/posts/sglang-disclosures/](https://thoughts.apoorvdayal.com/posts/sglang-disclosures/)

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