PatchSiren cyber security CVE debrief

CVE-2024-27024 Siemens CVE debrief

A vulnerability in the Linux kernel's Reliable Datagram Sockets (RDS) networking subsystem affects Siemens SIMATIC S7-1500 TM MFP industrial control systems. The issue involves improper connection state handling in `rds_conn_connect_if_down()`, where `get_mr()` can fail if a connection is not yet established, potentially triggering a WARNING condition. The vulnerability was published on April 9, 2024, and carries a HIGH severity CVSS 8.8 score with network attack vector, low attack complexity, and high impacts to confidentiality, integrity, and availability. Siemens has confirmed that currently no fix is available for this vulnerability in the affected GNU/Linux subsystem.

Vendor: Siemens
Product: SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
CVSS: HIGH 8.8
CISA KEV: Not listed in stored evidence
Original CVE published: 2024-04-09
Original CVE updated: 2026-05-14
Advisory published: 2024-04-09
Advisory updated: 2026-05-14

Who should care

Organizations operating Siemens SIMATIC S7-1500 TM MFP industrial control systems, particularly those utilizing the GNU/Linux subsystem for custom application deployment. OT security teams, industrial automation engineers, and critical infrastructure operators should prioritize access controls given the absence of an available patch.

Technical summary

The vulnerability exists in the Linux kernel's net/rds (Reliable Datagram Sockets) implementation. The function `rds_conn_connect_if_down()` contains a logic issue where `get_mr()` may fail if a connection has not been established, leading to a WARNING condition. The fix involves triggering the connection after `get_mr()` rather than before. This affects the GNU/Linux subsystem within Siemens SIMATIC S7-1500 TM MFP industrial controllers, which embed a Linux-based environment for running custom applications.

Defensive priority

HIGH

Recommended defensive actions

Limit access to the interactive shell of the additional GNU/Linux subsystem to trusted personnel only.
Only build and run applications from trusted sources.
Monitor for future security updates from Siemens for the SIMATIC S7-1500 TM MFP GNU/Linux subsystem.
Apply defense-in-depth strategies for industrial control systems per CISA guidance.

Evidence notes

Vulnerability description sourced from CISA CSAF advisory ICSA-24-102-01. Vendor attribution confirmed through CSAF product tree with high confidence. CVSS vector AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H indicates network-accessible attack with user interaction required.

Official resources

Public disclosure via CISA ICS advisory ICSA-24-102-01 and Siemens security advisory SSA-265688.