CVE-2025-27127: Siemens TIA Project-Server · Unrestricted File Upload
Affects Siemens TIA Project-ServerSource CVE Database V5
Public exploit available · CVSS 4.3 Medium.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 25% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:CExploitation evidence
Disclosed: evidence found.
CVE published 8 Jul 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: evidence found.
CVSS exploit maturity: proof of concept public
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CVSS vector, the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Siemens TIA Project-Server | Affected
| Fixed in– |
AI-suggested
European organizations should prioritize upgrading affected Siemens TIA Project-Server and TIA Portal installations to the latest versions that include fixes beyond V2.1.1 for Project-Server and V19 Update 4 or V20 Update 3 for TIA Portal. In the interim, organizations should enforce strict access controls to limit contributor privileges only to trusted personnel and implement monitoring to detect unusual file upload activities. Network segmentation should be applied to isolate TIA Project-Server systems from broader enterprise networks to reduce attack surface. Additionally, validating and restricting file types allowed for upload at the application or network level can help prevent malicious files from being accepted. Regular audits of user permissions and review of uploaded project files can detect potential abuse. Employing application-layer firewalls or intrusion detection systems with signatures for suspicious upload patterns may provide early warnings. Finally, Siemens customers should subscribe to Siemens security advisories to receive timely updates and patches.
Description
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.