Paper/Archive/CVE-2026-71268

CVE-2026-71268

thiagoralves OpenPLC_v3 — OpenPLC Runtime v3 Path Traversal in Structured Text FILE Directive Leading to Arbitrary File Write

EPSS 0.6%CVSS 9.9

critical.is priorityof 100

CVSS 9.9 (CNA)9.9 / 10 × 3029.7 Not in CISA KEV+300.0 EPSS percentile 47.7.477 × 209.5 No public exploit+100.0 SSVC exploitation: none+100.0

Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource

OpenPLC_v3≤ *–CNA

Scores by source

TuranSec (CNA)9.9CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

CISA ADPSSVCExploitation: none · Automatable: no · Technical impact: total

References

writeupgithub.com/thiagoralves/OpenPLC_v3 writeupgithub.com/thiagoralves/OpenPLC_v3/blob/master/webserver/openplc.py