End-of-life Linksys routers based on Realtek RTL819X chipsets are being actively exploited via CVE-2013-3307, a 2013-era OS command injection vulnerability, as part of the AryStinger botnet campaign. No vendor patch exists for end-of-life hardware. Any Linksys RTL819X-based router still in service must be treated as a confirmed compromise risk and scheduled for immediate replacement.