CVE-2026-33054
published 2026-03-20CVE-2026-33054: Mesop is a Python-based UI framework that allows users to build web applications. Versions 1.2.2 and below contain a Path Traversal vulnerability that allows…
PriorityP357critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.71%
49.0th percentile
Mesop is a Python-based UI framework that allows users to build web applications. Versions 1.2.2 and below contain a Path Traversal vulnerability that allows any user supplying an untrusted state_token through the UI stream payload to arbitrarily target files on the disk under the standard file-based runtime backend. This can result in application denial of service (via crash loops when reading non-msgpack target files as configurations), or arbitrary file manipulation. This vulnerability heavily exposes systems hosted utilizing FileStateSessionBackend. Unauthorized malicious actors could interact with arbitrary payloads overwriting or explicitly removing underlying service resources natively outside the application bounds. This issue has been fixed in version 1.2.3.
Affected
2 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mesop-dev | mesop | < 1.2.3 | 1.2.3 |
| mesop-dev | mesop | >= 0 < 1.2.3 | 1.2.3 |
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GHSA
Mesop has a Path Traversal utilizing `FileStateSessionBackend` leads to Application Denial of Service and File Write/Deletion
ghsa·2026-03-18
CVE-2026-33054 [CRITICAL] CWE-22 Mesop has a Path Traversal utilizing `FileStateSessionBackend` leads to Application Denial of Service and File Write/Deletion
Mesop has a Path Traversal utilizing `FileStateSessionBackend` leads to Application Denial of Service and File Write/Deletion
#### Summary
A Path Traversal vulnerability allows any user (or attacker) supplying an untrusted `state_token` through the UI stream payload to arbitrarily target files on the disk under the standard file-based runtime backend. This can result in application denial of service (via crash loops when reading non-msgpack target files as configurations), or arbitrary file manipulation.
#### Details
When the framework is configured to use the disk-based session backend (`FileStateSessionBackend`), the user's `state_token` actively dictates where the runtime session state is physically saved or queried natively on disk.
In `mesop/server/server.py`, specifically the `ui_s
OSV
Mesop has a Path Traversal utilizing `FileStateSessionBackend` leads to Application Denial of Service and File Write/Deletion
osv·2026-03-18
CVE-2026-33054 [CRITICAL] Mesop has a Path Traversal utilizing `FileStateSessionBackend` leads to Application Denial of Service and File Write/Deletion
Mesop has a Path Traversal utilizing `FileStateSessionBackend` leads to Application Denial of Service and File Write/Deletion
#### Summary
A Path Traversal vulnerability allows any user (or attacker) supplying an untrusted `state_token` through the UI stream payload to arbitrarily target files on the disk under the standard file-based runtime backend. This can result in application denial of service (via crash loops when reading non-msgpack target files as configurations), or arbitrary file manipulation.
#### Details
When the framework is configured to use the disk-based session backend (`FileStateSessionBackend`), the user's `state_token` actively dictates where the runtime session state is physically saved or queried natively on disk.
In `mesop/server/server.py`, specifically the `ui_s
No detection rules found.
No public exploits indexed.
2026-03-20
Published