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CVE-2024-50287 Siemens CVE debrief

A division-by-zero vulnerability exists in the Linux kernel's Video4Linux2 Test Pattern Generator (v4l2-tpg). The flaw occurs in the `tpg_precalculate_line()` function, which blindly rescales a buffer without validating that `scaled_width` is non-zero. This condition, detected by Coverity static analysis, can trigger a kernel crash when exploited by a local attacker with low privileges. The vulnerability affects Siemens industrial networking products running SINEC OS, specifically the RUGGEDCOM RST2428P and SCALANCE XC/XR/XCM/XRM/XCH/XRH families. Siemens has released firmware updates to address this issue.

Vendor
Siemens
Product
RUGGEDCOM RST2428P (6GK6242-6PA00)
CVSS
MEDIUM 5.5
CISA KEV
Not listed in stored evidence
Original CVE published
2025-08-12
Original CVE updated
2026-02-25
Advisory published
2025-08-12
Advisory updated
2026-02-25

Who should care

Organizations operating Siemens industrial networking infrastructure including RUGGEDCOM RST2428P switches and SCALANCE XC/XR/XCM/XRM/XCH/XRH family devices. OT security teams managing SINEC OS deployments in critical infrastructure environments. System administrators responsible for firmware maintenance of Siemens industrial Ethernet switches.

Technical summary

The vulnerability resides in the Video4Linux2 Test Pattern Generator (v4l2-tpg) component of the Linux kernel. The `tpg_precalculate_line()` function performs buffer rescaling operations without validating that the `scaled_width` parameter is non-zero. When `scaled_width` equals zero, the rescaling logic triggers a division-by-zero condition, resulting in a kernel crash and system availability impact. This is a local attack vector requiring low privileges with no user interaction. The CVSS 3.1 vector is AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H, indicating high availability impact but no confidentiality or integrity impact.

Defensive priority

medium

Recommended defensive actions

  • Apply vendor-provided firmware updates to affected Siemens industrial networking devices. For RUGGEDCOM RST2428P and SCALANCE XCM-/XRM-/XCH-/XRH-300 family devices, update to firmware version V3.2 or later. For SCALANCE
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Evidence notes

The vulnerability was identified through Coverity static analysis. The flaw is located in the Linux kernel's v4l2-tpg subsystem, specifically in the `tpg_precalculate_line()` function where buffer rescaling occurs without zero-check validation of the `scaled_width` parameter.

Official resources

2025-08-12