GHSA-pmww-v6c9-7p83 is a high-severity (CVSS 7.7) Cross-site Scripting (XSS) vulnerability in piccolo-admin. O3 Security confirms whether GHSA-pmww-v6c9-7p83 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Piccolo Admin's raw SVG loading may lead to complete data compromise from admin page
Real-World Exposure
piccolo-adminReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Summary
Piccolo's admin panel provides the ability to upload media files and view them within the admin panel. If SVG is an allowed file type for upload; the default; an attacker can upload an SVG which when loaded under certain contexts allows for arbitrary access to the admin page.
This access allows the following actions for example:
- The ability for an attacker to gain access to all data stored within the admin page
- The ability for an attacker to make any action within the admin page such as creating, modifying or deleting table records
As the SVG is executed from the context of an authenticated admin session, any actions they may be able to make can be made by the attacker.
N.b. The relevant session cookies are inaccessible from JavaScript due to httponly being set so all exploits must be present within the SVG file
PoC
Complete instructions, including specific configuration details, to reproduce the vulnerability.
Currently, this requires the ability for a user to have access to an administrators account in order to upload the malicious file for simplicity sake. I can however imagine situations where general end users have the ability to upload files which can later be managed via the admin page.
See the following repository: Piccolo XSS
- Clone the repo
- Run all migrations & create an admin user
- Run
app.pyas a FastAPI application - Login to the admin page
- Create a new task and upload the following file to see basic execution:
payloads/basic_xss.svg - Click the SVG to view it inline
- Click "Open image in new tab"
- Observe the XSS triggering
Fig 1: An example XSS payload executing
Extended PoC
This repo also includes an extended PoC which sends the Task table to an attacker controlled server.
- Run
exhil_server.pyas a FastAPI application - Upload the following payload:
payloads/exhil.svg - Open the SVG in a new tab and observe the data being sent to the attacker controlled server
Fig 2: An example screenshot from the attacker controlled server showing incoming data
Further, the repo includes a list of routes the admin panel exposes which could be used to automate table discovery and compromise in a more sophisticated PoC.
Impact
What kind of vulnerability is it? Who is impacted?
All applications with the following conditions present are affected:
- An enabled admin panel
- A model which features media upload that allows for SVG files
Further, if the site is behind a proxy of sorts it must not set the relevant security headers.
Further thoughts
While this issue has been raised against the piccolo_admin repository, it technically exists for all file uploads within a piccolo website if an end developer chooses to include the ability to view SVG files inline within their application. Further thought should likely be given to either or both of the following:
- Ensuring the documentation for media handling includes some form of warning/recommendation relating to this. Ideally I think it should just provide an example of a code fix and link to security headers to test their own application
- Modifying the Piccolo template generation to include the relevant security headers by default. These include things such as xss protection and a content security policy. This site is a great resource for testing the security headers set on a website
Given the need to allow end developers the freedom to allow for SVG upload, removing the ability to upload them entirely is likely out of the picture.
This could also be resolved by making attempts to view attachments in a new tab set the relevant content-disposition header and force the browser to download the file instead of rendering it inline of the website.
What are your thoughts on the approach to take to mitigate this?
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | piccolo-admin | ≥ 1.2.0&&< 1.3.2 | 1.3.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for piccolo-admin. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update piccolo-admin to 1.3.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-pmww-v6c9-7p83 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-pmww-v6c9-7p83 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-pmww-v6c9-7p83. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-pmww-v6c9-7p83 in your dependencies?
O3 detects GHSA-pmww-v6c9-7p83 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.