CVE-2026-27167Public exploitNetwork attack vector

Host token disclosure via mocked OAuth session

Published Feb 27, 2026 · Updated Feb 27, 2026

Credential exposure in Gradio 4.16.0 through 6.5.1 allows remote attackers to read the host's Hugging Face token through mocked OAuth. The attach_oauth flow registers _add_mocked_oauth_routes outside Spaces, and _get_mocked_oauth_info places huggingface_hub.get_token() in a base64-readable session cookie signed from the constant "-v4" secret. Exposure requires a network-accessible app using OAuth components, a configured host token, and the default missing OAUTH_CLIENT_SECRET.

CVSS severity5.9
Medium
EPSS probability0.45%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Credential exposure in Gradio 4.16.0 through 6.5.1 allows remote attackers to read the host's Hugging Face token through mocked OAuth. The attach_oauth flow registers _add_mocked_oauth_routes outside Spaces, and _get_mocked_oauth_info places huggingface_hub.get_token() in a base64-readable session cookie signed from the constant "-v4" secret. Exposure requires a network-accessible app using OAuth components, a configured host token, and the default missing OAUTH_CLIENT_SECRET.

The record

CVE
CVE-2026-27167
Published
Feb 27, 2026
Updated
Feb 27, 2026
Vendor
Gradio
Product
Gradio
Classifications
CWE-798, CWE-522, T1528
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 27, 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=>= 4.16.0, < 6.6.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Gradio · Gradioversion=>= 4.16.0, < 6.6.0

Published CVSS scores

0.0GitHub, Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:N
5.9NIST NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-798Use of Hard-coded Credentials
CWE-522Insufficiently Protected Credentials
T1528Steal Application Access Token

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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