CVE-2026-15974: SGLang SSRF and local file read in multimodal chat endpoint

CVE-2026-15974 · Severity: info · CVSS 7.5 · Published 2026-07-30

SGLang, an open-source framework for serving Large Language Models (LLMs), contains a vulnerability in its image processing component. By providing a specially crafted image URL to the chat completion service, an attacker can force the server to read local files or access internal network services that are not intended to be public. This could lead to the exposure of sensitive system files, internal metadata, or credentials stored on the server.

Technologies: SGLang Project SGLang. Vendors: SGLang Project.

Quick answers

Is CVE-2026-15974 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-15974 being exploited in the wild.
How severe is CVE-2026-15974?
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-2026-15974?
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-2026-15974 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-15974?
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 Server-Side Request Forgery (SSRF) and local file disclosure vulnerability exists in SGLang's multimodal generation endpoint (/v1/chat/completions). The root cause is the lack of input validation and sanitization on the 'image_url' parameter within the multimodal media loading logic. An unauthenticated or low-privileged attacker (depending on the server's API key configuration) can provide a URL pointing to local file paths (e.g., file:///etc/passwd) or internal network resources (e.g., cloud metadata services at 169.254.169.254). This allows for the exfiltration of local files, internal service discovery, and potential disclosure of secrets or internal metadata. The vulnerability is present in versions up to and including v0.5.15.

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 via CERT/CC and researcher blog.

References

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