Summary
Pterodactyl's improper JWT scoping allows subuser to upload files when not explicitly granted file.create permissions
A privilege escalation vulnerability exists in the Wings /upload/file endpoint due to insufficient validation of panel-signed JWTs. Wings accepts any valid panel-signed JWT containing server_uuid, user_uuid, and unique_id, regardless of the token’s intended purpose. Because the Panel issues JWTs with these same claims for other lower-privilege operations (such as WebSocket authentication and file download links), an authenticated subuser can reuse one of those tokens to upload arbitrary files without possessing the required file.create permission.
Details
The panel generated JWT tokens for various purposes:
- https://github.com/pterodactyl/panel/blob/0f82c105201b192d229f6abd5827e2ee7e672a05/app/Services/Backups/DownloadLinkService.php#L33-L36
- https://github.com/pterodactyl/panel/blob/0f82c105201b192d229f6abd5827e2ee7e672a05/app/Http/Controllers/Api/Client/Servers/FileUploadController.php#L45
- https://github.com/pterodactyl/panel/blob/0f82c105201b192d229f6abd5827e2ee7e672a05/app/Http/Controllers/Api/Client/Servers/WebsocketController.php#L58-L61
- https://github.com/pterodactyl/panel/blob/0f82c105201b192d229f6abd5827e2ee7e672a05/app/Http/Controllers/Api/Client/Servers/FileController.php#L82-L85
Though as the actual purpose is not conveyed part of the JWT tokens, this introduces this vulnerability of being able to do non-intended actions due to the expected fields (i.e.server_uuid) on most endpoints being the same when parsing it on wings' side.
PoC
Create a new subuser that has the minimal amount of permissions on a server (websocket.connect). As that subuser, retrieve a websocket JWT token from the GET /api/client/servers/[...]/websocket endpoint (in my case, I manually just make a request under that user's browser session; you can probably just resend the /websocket request in browser console to get a fresh unused token). Using that websocket token, we can abuse this by directly using it in the /upload/file endpoint of the wings node instead of using it for websocket authentication:
import requests
wings_url = 'http://[...]:8080'
websocket_token = '[...]'
res = requests.post(f'{wings_url}/upload/file', params = {
'token': websocket_token,
}, files = {
'files': ('file-upload.txt', b'Hello, World!'),
})
print(res.status_code, res.content)
Observe, that even though our subuser never has permissions outside viewing the console, they are able to write arbitrary files in the server. This pattern happens in a lot of other action, but this is probably the most interesting one.
Impact
Any subuser with permission to connect to a server's console, download files, or download backups could reuse those tokens to upload arbitrary files to the same server. A user that does not have access to a server as a subuser is not able to arbitrarily upload files.
CVE-2026-54593 has a CVSS score of 8.1 (High). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.12.3, 1.12.2); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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pterodactyl/panel to 1.12.3 or later; github.com/pterodactyl/wings to 1.12.2 or later
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2026-54593? CVE-2026-54593 is a high-severity security vulnerability in pterodactyl/panel (composer), affecting versions < 1.12.3. It is fixed in 1.12.3, 1.12.2.
- How severe is CVE-2026-54593? CVE-2026-54593 has a CVSS score of 8.1 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which packages are affected by CVE-2026-54593?
pterodactyl/panel(composer) (versions < 1.12.3)github.com/pterodactyl/wings(go) (versions < 1.12.2)
- Is there a fix for CVE-2026-54593? Yes. CVE-2026-54593 is fixed in 1.12.3, 1.12.2. Upgrade to this version or later.
- Is CVE-2026-54593 exploitable, and should I be worried? Whether CVE-2026-54593 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-54593 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-54593?
- Upgrade
pterodactyl/panelto 1.12.3 or later - Upgrade
github.com/pterodactyl/wingsto 1.12.2 or later
- Upgrade