What is CVE-2025-27127?
A vulnerability has been identified in TIA Project-Server (All versions < V2.1.1), TIA Project-Server V17 (All versions), Totally Integrated Automation Portal (TIA Portal) V17 (All versions), Totally Integrated Automation Portal (TIA Portal) V18 (All versions), Totally Integrated Automation Portal (TIA Portal) V19 (All versions < V19 Update 4), Totally Integrated Automation Portal (TIA Portal) V20 (All versions < V20 Update 3). The affected application improperly handles uploaded projects in the document root. This could allow an attacker with contributor privileges to cause denial of service by uploading a malicious project.
The record classifies CVE-2025-27127 under weakness class CWE-434. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs low-privilege credentials, needs no user interaction. 6 affected-product entries are recorded, across 1 vendor, listed below. The identifier was first published 464 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 4.3 — MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C - CVSS v4.0 base score
- 5.3
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N - EPSS (FIRST)
- 0.3% probability of exploitation in the next 30 days, higher than 23.5% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 3.1/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2025-07-08, last modified 2025-08-12
Is CVE-2025-27127 being exploited?
It currently carries a trending score of 11 in the Threadlinqs vulnerability feed.
Affected products and versions
- Siemens: TIA Project-Server, TIA Project-Server V17, Totally Integrated Automation Portal (TIA Portal) V17, Totally Integrated Automation Portal (TIA Portal) V18, Totally Integrated Automation Portal (TIA Portal) V19, Totally Integrated Automation Portal (TIA Portal) V20
How to fix CVE-2025-27127
No vendor patch reference has been recorded for CVE-2025-27127 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-2025-27127
1 tracked threat in the Threadlinqs corpus references CVE-2025-27127, 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, GitHub Security Advisories. Last verified by Threadlinqs on .