Path Traversal in Thiagoralves Openplc V3

CVE-2026-71268

OpenPLC Runtime v3's compile_program function (webserver/openplc.py) parses directives from uploaded Structured Text (.st) program files and writes the referenced content to with no validation that file_path stays within the ./core directory. A path-validation function, validate_file_path, exists elsewhere in the codebase (webserver/credentials.py) but is never invoked from compile_program, leaving the sink unprotected.

Vulnerability class: Path Traversal (Directory Traversal)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.006 (47.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 48th percentile — 47.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-71268: held from 0.006 to 0.006.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-71268?
CVE-2026-71268 is a critical-severity vulnerability in Thiagoralves Openplc V3, classified under Path Traversal. CVSS score: 9.9/10. Published 2026-08-05.
How severe is CVE-2026-71268?
Critical severity. CVSS v3 base score is 9.9 out of 10.