CVE-2025-29931: 
Telecontrol Server Basic vulnerability analysis and mitigation

A vulnerability (CVE-2025-29931) has been identified in TeleControl Server Basic (versions prior to V3.1.2.2). The vulnerability relates to improper validation of length fields in serialized messages, which affects memory allocation during deserialization. This vulnerability was discovered by Jin Huang from ADLab of Venustech and was disclosed on April 17, 2025 (Siemens Advisory).

The vulnerability stems from improper handling of length parameter inconsistency (CWE-130) in the TeleControl Server Basic system. When processing serialized messages, the application fails to properly validate length fields used for memory allocation during deserialization. The vulnerability has received a CVSS v3.1 base score of 3.7 (LOW) with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L, and a CVSS v4.0 score of 6.3 (MEDIUM) with vector string CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N (CISA Advisory).

If successfully exploited, this vulnerability could allow an unauthenticated remote attacker to cause the application to allocate exhaustive amounts of memory, resulting in a partial denial-of-service (DoS) condition. The impact is limited to redundant TeleControl Server Basic setups and only occurs when the connection between redundant servers has been disrupted (Siemens Advisory).

Siemens has released version V3.1.2.2 to address this vulnerability and recommends updating to this or a later version. As a workaround, organizations can disable TeleControl Server Basic redundancy if not in use. Additionally, Siemens recommends protecting network access to devices with appropriate mechanisms and configuring the environment according to Siemens' operational guidelines for Industrial Security (Siemens Advisory).

The vulnerability has gained attention in the industrial control systems security community, with CISA releasing an advisory as part of a broader set of ICS vulnerability announcements. The relatively low severity score and specific exploitation conditions have resulted in measured concern from the security community (Cybersecurity News).