Staging Environment: Content and features may be unstable or change without notice.
Advisory details: pypa / gradio/PYSEC-2026-63
Advisory ID pypa/gradio/PYSEC-2026-63
Aliases CVE-2026-27167
GHSA-h3h8-3v2v-rg7m
PYSEC-2026-63
Summary Gradio is an open-source Python package designed for quick prototyping. Starting in version 4.16.0 and prior to version 6.6.0, Gradio applications running outside of Hugging Face Spaces automatically enable "mocked" OAuth routes when OAuth components (e.g. `gr.LoginButton`) are used. When a user visits `/login/huggingface`, the server retrieves its own Hugging Face access token via `huggingface_hub.get_token()` and stores it in the visitor's session cookie. If the application is network-accessible, any remote attacker can trigger this flow to steal the server owner's HF token. The session cookie is signed with a hardcoded secret derived from the string `"-v4"`, making the payload trivially decodable. Version 6.6.0 fixes the issue.
Status Published
Exploitability 0.5
Weighted Severity 5.3
Risk 2.6
Affected and Fixed Packages Package Details
Introduced and Fixed Package Commit Patches Package Commit Patches Details
Weaknesses (0)
There are no known CWE.
System Score Found at
cvssv3.1 5.9 https://github.com/pypa/advisory-database/blob/main/vulns/gradio/PYSEC-2026-63.yaml
Reference id Reference type URL
GHSA-h3h8-3v2v-rg7m https://github.com/gradio-app/gradio/security/advisories/GHSA-h3h8-3v2v-rg7m
No exploits are available.

No EPSS data available for this advisory.

Patch URL
There are no known patches.
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N Found at https://github.com/pypa/advisory-database/blob/main/vulns/gradio/PYSEC-2026-63.yaml
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none

Vector: SSVCv2/E:P/A:N/T:P/P:M/B:A/M:M/D:T/2026-03-02T22:02:38Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/27xxx/CVE-2026-27167.json

Source Advisory: vulnrichment/CVE-2026-27167

View SSVC decision tree 
[{'Exploitation': 'poc'},
 {'Automatable': 'no'},
 {'Technical Impact': 'partial'},
 {'Mission Prevalence': 'minimal'},
 {'Public Well-being Impact': 'material'},
 {'Mission & Well-being': 'medium'}]

Vector: SSVCv2/E:P/A:N/T:P/P:M/B:A/M:M/D:T/2026-03-02T22:02:38Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/27xxx/CVE-2026-27167.json

Source Advisory: vulnrichment/CVE-2026-27167

View SSVC decision tree 
[{'Exploitation': 'poc'},
 {'Automatable': 'no'},
 {'Technical Impact': 'partial'},
 {'Mission Prevalence': 'minimal'},
 {'Public Well-being Impact': 'material'},
 {'Mission & Well-being': 'medium'}]