CVE-2026-3059: Sglang Remote Code Execution Vulnerability

CRITICAL
Advisory Identifier: GHSA-rgq9-fqf5-fv58
CVSS 9.8
CWE-502
Published
Advisory Summary

CVE-2026-3059 is a CRITICAL (CVSS 9.8) remote code execution vulnerability (CWE-502: Deserialization of Untrusted Data) affecting Sglang libraries in the PyPI ecosystem. The issue involves sglang's multimodal generation module is vulnerable to unauthenticated remote code execution through the zmq broker. Remediation is available by upgrading affected packages to version 0.5.10.

CVE-2026-3059 at a Glance

CVE Identifier CVE-2026-3059
GHSA Identifier GHSA-rgq9-fqf5-fv58
Severity CRITICAL
CVSS v3.1 Base Score 9.8
CWE Classification CWE-502: Deserialization of Untrusted Data
Affected Product Sglang
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 9.8

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2026-3059

To remediate this vulnerability, upgrade all affected Sglang dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

sglang fixed: 0.5.10
pip install sglang>=0.5.10
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

pip show sglang

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2026-3059, inspect your installed packages using pip:

pip show sglang

Analyze the terminal output to locate any version of Sglang in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.5.10), your application is affected.

Note: The pip show sglang command checks currently installed packages in your active Python environment.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-502: Deserialization of Untrusted Data, where the product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid. In Sglang, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

SGLang's multimodal generation module is vulnerable to unauthenticated remote code execution through the ZMQ broker, which deserializes untrusted data using pickle.loads() without authentication.

CVE-2026-3059 Affected Sglang Versions

1 component(s)
Fixed Versions:
0.5.10
Product / Package Ecosystem Affected Versions Fixed Version
sglang
PyPI
< 0.5.10
0.5.10

References

Frequently Asked Questions

What is CVE-2026-3059?
CVE-2026-3059 is a security vulnerability in Sglang involving SGLang's multimodal generation module is vulnerable to unauthenticated remote code execution through the ZMQ broker under CWE-502: Deserialization of Untrusted Data.
Which Sglang versions are affected?
Affected versions include releases prior to 0.5.10 across affected packages: sglang.
What version fixes CVE-2026-3059?
Upgrading to 0.5.10 (or the latest patched release for your respective branch) resolves the vulnerability.
Is sglang affected?
Yes, sglang is affected in releases prior to 0.5.10. Upgrade your dependency to 0.5.10 or later.
What is the CVSS score of CVE-2026-3059?
CVE-2026-3059 has a CVSS v3.1 base score of 9.8 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2026-3059?
CVE-2026-3059 is classified under CWE-502: Deserialization of Untrusted Data (The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.).
How can I check PyPI dependencies for CVE-2026-3059?
Run the dependency tree command: 'pip show sglang'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-rgq9-fqf5-fv58",
  "modified" : "2026-04-07T22:14:24Z",
  "published" : "2026-03-12T12:30:29Z",
  "aliases" : [ "CVE-2026-3059" ],
  "summary" : "SGLang's multimodal generation module is vulnerable to unauthenticated remote code execution through the ZMQ broker",
  "details" : "SGLang's multimodal generation module is vulnerable to unauthenticated remote code execution through the ZMQ broker, which deserializes untrusted data using pickle.loads() without authentication.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "sglang"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.5.10"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 0.5.9"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/sgl-project/sglang/security/advisories/GHSA-3cp7-c6q2-94xr"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-3059"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/sgl-project/sglang/pull/20904"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/sgl-project/sglang"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/sgl-project/sglang/blob/main/python/sglang/multimodal_gen/runtime/scheduler_client.py"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/sgl-project/sglang/releases/tag/v0.5.10"
  }, {
    "type" : "WEB",
    "url" : "https://orca.security/resources/blog/sglang-llm-framework-rce-vulnerabilities"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-502" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-12T17:38:58Z",
    "nvd_published_at" : "2026-03-12T12:15:59Z"
  }
}