vulnerability / NVI-00016246 / Revision 1
Gogs's Unauthenticated Jupyter Notebook (ipynb) Sanitizer allows arbitrary data: URIs leading to XSS
GitHub lists this reviewed advisory for gogs.io/gogs. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
gogs.io/gogs
source listed< 0.14.3
## Summary The Jupyter Notebook (ipynb) sanitizer endpoint at `POST /-/api/sanitize_ipynb` allows arbitrary `data:` URIs without proper restrictions, potentially leading to Cross-Site Scripting (XSS). The endpoint uses `bluemonday.UGCPolicy()` with `p.AllowURLSchemes("data")` which permits all data URI schemes including `data:text/html`, enabling attackers to inject malicious HTML/JavaScript. Additionally, the endpoint has no authentication middleware, allowing any registered user to exploit this vulnerability. ## Severity **High** ## Affected Versions All versions using the vulnerable endpoint ## Vulnerability Details - **CVE ID**: (To be assigned) - **Entry Point**: `POST /-/api/sanitize_ipynb` - **Attack Vector**: Network - **Authentication Required**: No (only needs a registered user account) ## Impact An attacker with a registered user account can: - Send malicious HTML containing `data:text/html` URIs to the sanitization endpoint - Receive sanitized but attacker-controlled HTML in the response - Execute arbitrary JavaScript in the attacker's browser context through XSS - Potentially exploit other users if the sanitized output is rendered in their context The vulner
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
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04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
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- GHSA-3w28-36p9-w929 ↗
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Public revision history
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- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.