The Yadea T5 Electric Bicycle models manufactured in or after 2024 expose a weak authentication mechanism in their keyless entry system. The system relies on the EV1527 fixed-code RF protocol and lacks both rolling codes and cryptographic challenge-response. This design flaw allows a local attacker who intercepts a legitimate key fob transmission to forge the signal and replay it, resulting in complete unauthorized vehicle operation. The compromised security property is the integrity of the access control system, as highlighted by CWE‑1390.

Yadea T5 Electric Bicycles (models manufactured in or after 2024).

The vulnerability carries a CVSS score of 7.3, indicating a high severity. The EPSS score of less than 1% suggests that the practical likelihood of exploitation is currently very low, and the flaw is not listed in the CISA KEV catalog. However, the attack vector requires a local presence to intercept the key fob signal, after which the attacker can replay the captured RF transmission to gain unauthorized control of the bicycle. If an adversary can be near the vehicle, they could potentially operate it without authorization, posing a threat to owner safety and property.