CVE-2026-15977: SGLang credential leakage in server_info endpoint

CVE-2026-15977 · Severity: info · CVSS 7.5 · Published 2026-07-30

SGLang, an open-source framework for serving Large Language Models (LLMs), contains a security flaw where sensitive credentials can be exposed. The system's information endpoint incorrectly shares administrative API keys and SSL certificate passwords with unauthorized users. An attacker who can reach the server over the network could use this information to gain full administrative control over the AI model server or intercept encrypted traffic.

Technologies: SGLang Project SGLang. Vendors: SGLang Project.

Quick answers

Is CVE-2026-15977 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-15977 being exploited in the wild.
How severe is CVE-2026-15977?
Informational severity, with a CVSS score of 7.5, published 30 July 2026.
Which products and versions are affected?
SGLang Project SGLang <= v0.5.15.
Is there a fix for CVE-2026-15977?
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-2026-15977 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-15977?
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 credential leakage vulnerability exists in SGLang's '/server_info' and '/get_server_info' endpoints due to improper authorization checks and over-broad data serialization. The root cause is twofold: first, the endpoint lacks an explicit '@auth_level' decorator, causing the middleware to default to 'AuthLevel.NORMAL', which does not restrict access when only an '--admin-api-key' is configured. Second, the endpoint serializes the entire server configuration object using 'dataclasses.asdict(server_args)', which includes sensitive fields like 'api_key', 'admin_api_key', and 'ssl_keyfile_password'. An unauthenticated attacker can exploit this to retrieve the administrative API key, subsequently gaining full access to administrative routes and management functions.

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

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