CVE-2026-58196Public exploitNetwork attack vectorHinoki check available

Internal HTTP access via unguarded authentication discovery

Published Sep 15, 2026 · Updated Sep 15, 2026

SSRF in ToolHive before 0.31.0 allows remote attackers to make host-side GET requests to internal services through authentication discovery. FetchResourceMetadata and the OIDC discovery clients trust server-supplied metadata destinations, follow redirects across hosts or schemes, and omit private-address filtering. Exploitation requires an operator to connect to a malicious or compromised remote MCP server; the server can probe internal HTTP services and read responses, including AWS metadata credentials when IMDSv1 permits unauthenticated GET requests.

CVSS severity4.7
Medium
EPSS probability0.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

SSRF in ToolHive before 0.31.0 allows remote attackers to make host-side GET requests to internal services through authentication discovery. FetchResourceMetadata and the OIDC discovery clients trust server-supplied metadata destinations, follow redirects across hosts or schemes, and omit private-address filtering. Exploitation requires an operator to connect to a malicious or compromised remote MCP server; the server can probe internal HTTP services and read responses, including AWS metadata credentials when IMDSv1 permits unauthenticated GET requests.

The record

CVE
CVE-2026-58196
Published
Sep 15, 2026
Updated
Sep 15, 2026
Vendor
Stacklok
Product
ToolHive
Classifications
CWE-918
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 0.31.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Stacklok · ToolHiveversion=< 0.31.0

Published CVSS scores

4.7OSVCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N
2.9GitHub Advisory DatabaseCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-918Server-Side Request Forgery (SSRF)

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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