What is CVE-2025-40943?
Affected devices do not properly sanitize contents of trace files. This could allow an attacker to inject code through social engineering an authorized user, who has the function right "Read diagnostics", to import a specially crafted trace file. The malicious trace file is insufficiently sanitized and malicious code could be executed in the clients browser session and trigger PLC operations via the webserver that the legitimate user is authorized to perform.
The record classifies CVE-2025-40943 under weakness class CWE-95. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs a user to take an action first, and has high impact on confidentiality, integrity, availability. 12 affected-product entries are recorded, across 1 vendor, listed below. The identifier was first published 219 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 9.6 — CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H - CVSS v4.0 base score
- 9.4
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H - EPSS (FIRST)
- 0.4% probability of exploitation in the next 30 days, higher than 39.1% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 6.4/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2026-03-10, last modified 2026-05-12
Is CVE-2025-40943 being exploited?
It currently carries a trending score of 15 in the Threadlinqs vulnerability feed.
Affected products and versions
- Siemens: SIMATIC Drive Controller CPU 1504D TF, SIMATIC Drive Controller CPU 1507D TF, SIMATIC ET 200SP CPU 1510SP F-1 PN, SIMATIC ET 200SP CPU 1510SP-1 PN, SIMATIC ET 200SP CPU 1512SP F-1 PN, SIMATIC ET 200SP CPU 1512SP-1 PN, SIMATIC ET 200SP CPU 1514SP F-2 PN, SIMATIC ET 200SP CPU 1514SP-2 PN, SIMATIC ET 200SP CPU 1514SPT F-2 PN, SIMATIC ET 200SP CPU 1514SPT-2 PN, SIMATIC ET 200SP Open Controller CPU 1515SP PC (incl. SIPLUS variants), SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants) V2 CPUs - Windows OS
How to fix CVE-2025-40943
No vendor patch reference has been recorded for CVE-2025-40943 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.
Threat activity tracking CVE-2025-40943
1 tracked threat in the Threadlinqs corpus references CVE-2025-40943, either in the campaign’s CVE list or as an indicator on the campaign record.
- AI-Powered Attacks Targeting Siemens S7 Series PLCs in U.S. Critical Infrastructure — CRITICAL · 2026-08-19
Sources
Enriched from CVE.org, FIRST EPSS. Last verified by Threadlinqs on .