CVE-2025-40771: Siemens SIMATIC CP 1542SP-1 · Missing Authentication
Affects Siemens SIMATIC CP 1542SP-1Source CVE Database V5
Not known to be exploited · CVSS 9.8 Critical.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 44% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 14 Oct 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
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), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Siemens SIMATIC CP 1542SP-1 | Affected
| Fixed in– |
AI-suggested
- Immediately upgrade all affected Siemens SIMATIC CP 1542SP-1 and related devices to firmware version 2.4.24 or later once Siemens releases the patch.
- Until patches are applied, implement strict network segmentation to isolate these devices from untrusted networks and limit access to trusted management stations only.
- Employ firewall rules and access control lists (ACLs) to restrict configuration port access to authorized IP addresses.
- Monitor network traffic for unusual connection attempts to the configuration interfaces of these devices.
- Use industrial intrusion detection systems (IDS) tailored to detect unauthorized configuration access attempts.
- Conduct regular audits of device configurations and logs to detect unauthorized changes.
- Engage with Siemens support for any interim mitigation guidance or firmware updates.
- Incorporate this vulnerability into incident response plans specific to industrial control systems to ensure rapid containment if exploited.
Description
A vulnerability has been identified in SIMATIC CP 1542SP-1 (6GK7542-6UX00-0XE0) (All versions < V2.4.24), SIMATIC CP 1542SP-1 IRC (6GK7542-6VX00-0XE0) (All versions < V2.4.24), SIMATIC CP 1543SP-1 (6GK7543-6WX00-0XE0) (All versions < V2.4.24), SIPLUS ET 200SP CP 1542SP-1 IRC TX RAIL (6AG2542-6VX00-4XE0) (All versions < V2.4.24), SIPLUS ET 200SP CP 1543SP-1 ISEC (6AG1543-6WX00-7XE0) (All versions < V2.4.24), SIPLUS ET 200SP CP 1543SP-1 ISEC TX RAIL (6AG2543-6WX00-4XE0) (All versions < V2.4.24). Affected devices do not properly authenticate configuration connections. This could allow an unauthenticated remote attacker to access the configuration data.