Siemens Interniche IP-Stack TCP Sequence Vulnerability
⚠️Siemens warns of a TCP sequence validation flaw in the Interniche IP-Stack (CVE-2025-40820) that can allow unauthenticated remote actors to interfere with TCP connection setup and cause denial of service. The defect accepts a broad range of sequence values, permitting precisely timed spoofed packets to disrupt TCP-based services. Siemens has released fixes for many affected SKUs and recommends updating to the published firmware versions; where fixes are not yet available, follow the vendor’s countermeasures and apply network controls to limit exposure.
