CVE-2025-34450 identifies a stack-based buffer overflow vulnerability in the popular open-source software rtl_433, maintained by merbanan, which is used for decoding various radio frequency (RF) signals. The vulnerability resides in the parse_rfraw() function within src/rfraw.c, where the application improperly handles raw RF input data. Specifically, when rtl_433 processes crafted or excessively large raw RF data, it writes beyond the allocated stack buffer boundaries, leading to memory corruption. This can cause the application to crash (denial of service) or, under certain conditions, enable an attacker to execute arbitrary code or escalate privileges depending on the runtime environment and existing security mitigations such as stack canaries, ASLR, and DEP. The vulnerability affects all versions up to and including 25.02 and prior to commit 25e47f8. Exploitation does not require authentication, user interaction, or privileges but does require local access to feed malicious RF data into the system running rtl_433. The CVSS 4.0 vector (AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N) reflects that the attack vector is local, with low complexity, no privileges or user interaction needed, no impact on confidentiality, integrity, or availability beyond denial of service, but with high impact on availability. No public exploits or patches are currently available, emphasizing the importance of monitoring for updates and applying defensive controls.

The primary impact of CVE-2025-34450 is denial of service due to application crashes triggered by buffer overflow. In environments where rtl_433 is used for critical RF signal decoding—such as IoT device monitoring, home automation, weather stations, or industrial sensor networks—this can disrupt operations and data collection. More severe exploitation could allow attackers to execute arbitrary code or escalate privileges, potentially compromising the host system. This risk is heightened in embedded or IoT devices with rtl_433 integrated, where patching may be delayed or difficult. Organizations relying on rtl_433 for security monitoring or operational control may face service interruptions or security breaches. The vulnerability's local attack vector limits remote exploitation but does not eliminate risk in multi-tenant or shared environments where untrusted users can supply RF input. Overall, the threat could impact availability and system integrity, with potential cascading effects on dependent systems and services.

To mitigate CVE-2025-34450, organizations should: 1) Upgrade rtl_433 to a version that includes the fix for this vulnerability once available, monitoring the official repository and security advisories for patches. 2) Implement strict input validation and filtering on RF data sources to prevent injection of malformed or excessively large raw RF inputs. 3) Restrict access to rtl_433 instances, ensuring only trusted users or systems can feed RF data, minimizing exposure to crafted inputs. 4) Employ runtime protections such as stack canaries, address space layout randomization (ASLR), and data execution prevention (DEP) on hosts running rtl_433 to reduce exploitation likelihood. 5) Monitor application logs and system behavior for crashes or anomalies indicative of attempted exploitation. 6) In embedded or IoT deployments, establish secure update mechanisms to facilitate timely patching. 7) Consider network segmentation or isolation of rtl_433 systems to limit attack surface. These targeted measures go beyond generic advice by focusing on controlling input sources, hardening runtime environments, and ensuring rapid patch deployment.