{"cve":"CVE-2026-33054","nvd":{"published":"2026-03-20T07:16:13.363","modified":"2026-06-17T10:36:52.323","status":"Analyzed","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":["CWE-22"],"references":["https://github.com/mesop-dev/mesop/commit/c6b382f363b73ac32c402a2db3aadc7784f66a5b","https://github.com/mesop-dev/mesop/releases/tag/v1.2.3","https://github.com/mesop-dev/mesop/security/advisories/GHSA-8qvf-mr4w-9x2c","https://github.com/mesop-dev/mesop/security/advisories/GHSA-8qvf-mr4w-9x2c"],"products":["mesop-dev:mesop"],"source":"nvd","synced_at":"2026-10-19T22:26:19.218427112+00:00"},"epss":{"cve":"CVE-2026-33054","score":0.00725,"percentile":0.54108,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-8qvf-mr4w-9x2c","url":"https://osv.dev/vulnerability/GHSA-8qvf-mr4w-9x2c","summary":"Mesop has a Path Traversal utilizing `FileStateSessionBackend` leads to Application Denial of Service and File Write/Deletion","modified":"2026-06-29T12:26:27.961763680Z","packages":[{"ecosystem":"PyPI","name":"mesop","purl":"pkg:pypi/mesop","ranges":["<1.2.3"],"fixed":["1.2.3"]}]},{"id":"PYSEC-2026-411","url":"https://osv.dev/vulnerability/PYSEC-2026-411","summary":"Mesop has a Path Traversal utilizing `FileStateSessionBackend` leads to Application Denial of Service and File Write/Deletion","modified":"2026-07-13T16:15:28.237924103Z","packages":[{"ecosystem":"PyPI","name":"mesop","purl":"pkg:pypi/mesop","ranges":["<1.2.3"],"fixed":["1.2.3"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}