PatchSiren cyber security CVE debrief

CVE-2022-45886 Siemens CVE debrief

A use-after-free vulnerability exists in the Linux kernel's DVB (Digital Video Broadcasting) networking subsystem, specifically in drivers/media/dvb-core/dvb_net.c. The flaw stems from a race condition between the .disconnect handler and dvb_device_open operations. An attacker with local access could potentially exploit this timing window to trigger memory corruption, leading to privilege escalation or system instability. The vulnerability affects Linux kernel versions through 6.0.9. Siemens has identified this issue as affecting their TIM 1531 IRC industrial communication modules, which incorporate the vulnerable kernel component. The CVSS 3.1 score of 7.0 (HIGH) reflects significant impact potential (confidentiality, integrity, and availability) though exploitation requires local access and high attack complexity.

Vendor: Siemens
Product: SIPLUS TIM 1531 IRC (6AG1543-1MX00-7XE0)
CVSS: HIGH 7
CISA KEV: Not listed in stored evidence
Original CVE published: 2024-06-11
Original CVE updated: 2024-07-09
Advisory published: 2024-06-11
Advisory updated: 2024-07-09

Who should care

Organizations operating Siemens TIM 1531 IRC industrial communication modules in OT/ICS environments; system administrators managing embedded Linux devices with DVB capabilities; security teams responsible for kernel-level vulnerability management in industrial control systems.

Technical summary

The vulnerability resides in the DVB (Digital Video Broadcasting) core networking driver (dvb_net.c) within the Linux kernel media subsystem. A race condition between device disconnection and open operations can result in a use-after-free condition, where memory is accessed after it has been freed. This class of vulnerability typically enables attackers to corrupt kernel memory structures, potentially achieving arbitrary code execution in kernel context. The attack surface is constrained by the requirement for local access and the inherent difficulty of winning the race condition, as reflected in the AC:H (Attack Complexity: High) CVSS metric.

Defensive priority

HIGH

Recommended defensive actions

Apply vendor-provided firmware update to version V2.4.8 or later for affected Siemens TIM 1531 IRC and SIPLUS TIM 1531 IRC devices
Review and implement CISA ICS recommended practices for defense-in-depth strategies
Monitor for anomalous system behavior or unexpected crashes on affected industrial communication modules
Restrict physical and logical access to affected devices to authorized personnel only
Validate kernel version on embedded Linux systems and coordinate with vendors for patch availability

Evidence notes

CVE published 2024-06-11; modified 2024-07-09. CISA ICS advisory ICSA-24-165-06 published same date. Siemens SSA-337522 provides vendor-specific guidance.

Official resources

2024-06-11