CVE-2026-33054
Mesop is a Python-based UI framework that allows users to build web applications.
Published Mar 20, 2026 · updated Jun 17, 2026 · mesop-dev mesop
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.
Code
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Timeline
Detection, updates, and resolution for this record.
Mar 20, 2026 · NIST NVD
Detected
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 no
Jun 17, 2026 · NIST NVD
Updated
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 no
Affected
- cpe mesop-dev/mesopversion unspecified
Sources
- CVE.orgVulnerability recordCVE-2026-33054
Official CVE identifier
cve.org - NIST NVDVulnerability recordCVE-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 any user supplying an untrusted state_token through the UI stream payload to arbitrarily target files on the disk under th
nvd.nist.gov