An out-of-bounds read/write vulnerability when executing lazily compiled inner generator functions in Facebook Hermes prior to commit 091835377369c8fd5917d9b87acffa721ad2a168 allows attackers to potentially execute arbitrary code via crafted JavaScript. Note that this is only exploitable if the application using Hermes permits evaluation of untrusted JavaScript. Hence, most React Native applications are not affected.

An Integer signedness error in the JavaScript Interpreter in Facebook Hermes prior to commit 2c7af7ec481ceffd0d14ce2d7c045e475fd71dc6 allows attackers to cause a denial of service attack or a potential RCE via crafted JavaScript. Note that this is only exploitable if the application using Hermes permits evaluation of untrusted JavaScript. Hence, most React Native applications are not affected.