rtl_433: Stack-based buffer overflow in proflame2_mc (CVE-2026-117609)

A stack-based buffer overflow vulnerability exists in the proflame2_mc() function of rtl_433 (all versions through 25.12). The issue occurs when the application processes more than seven Manchester-coded words. An attacker within radio range can transmit a crafted On-Off Keying (OOK) signal or provide a malformed signal file to trigger the overflow. This can result in application crashes or, if the binary is compiled without stack canaries, potential control-flow hijacking.

Impact

Successful exploitation allows for the crash of the rtl_433 service or potential arbitrary code execution, depending on the compiler protections enabled for the specific deployment.

Recommendation

• Upgrade rtl_433 to a version that patches the proflame2_mc() function, or monitor the project repository for the official security release addressing this vulnerability.
• Audit current deployments to determine if they are compiled with stack protection (e.g., -fstack-protector or -fstack-protector-strong) to mitigate the risk of arbitrary code execution.
• Restrict the input sources for rtl_433 if possible, particularly by verifying the integrity of signal capture files before processing them.