On Reolink RLC-410W, C1 Pro, C2 Pro, RLC-422W, and RLC-511W devices through 1.0.227, an authenticated admin can use the "TestEmail" functionality to inject and run OS commands as root, as demonstrated by shell metacharacters in the addr1 field.
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-11001