DD‑WRT firmware on TP‑Link TL‑WR740N routers of hardware variants v1 through v4 stores authentication credentials in cleartext inside non‑volatile SPI flash memory. The exposed data includes SSH private keys, dynamic DNS passwords, email notification credentials, and administrative passwords. An attacker who can access the device’s flash memory can recover all of these credentials, effectively compromising the router, gaining administrative authority, and potentially isolating the connected network and any downstream services that rely on those stored keys.

The affected systems are TP‑Link TL‑WR740N routers of hardware variants v1 through v4 running any DD‑WRT firmware build that includes this cleartext storage bug. Administrators of home or small‑business networks should verify whether their routers are running DD‑WRT and whether the firmware contains this flaw.

The EPSS score is less than 1 % and the CVE is not listed in the CISA KEV catalog, indicating a low probability of widespread exploitation at present. The attack vector requires physical access to the device so that the attacker can perform an SPI flash dump. If the credentials are extracted, the attacker gains full control of the router, can infiltrate the connected network, and may abuse third‑party services authenticated with those credentials. The CVSS score of 7.6 highlights a high severity that reflects significant potential impact once the device is compromised.