Critical Firefox Vuln Used in Targeted Attacks

Mozilla has patched a critical vulnerability under active exploit in the Firefox browser. 

Digital currency exchange Coinbase reported the vulnerability to Mozilla after discovering it in use for targeted attacks. According to the Mozilla advisory, the type confusion vulnerability (CVE-2019-11707) "can occur when manipulating JavaScript objects due to issues in Array.pop. This can allow for an exploitable crash." 

The researcher who discovered the flaw – Samuel Groß of Google Project Zero and Coinbase Security – stated on Twitter: "The bug can be exploited for RCE but would then need a separate sandbox escape. However, most likely it can also be exploited for UXSS which might be enough depending on the attacker's goals."

The vulnerability has been fixed in Firefox 67.0.3 and Firefox ESR 60.7.1. Read more here and here.