An issue was discovered in ProxyServlet.java in the /proxy servlet in Zimbra Collaboration Suite 8.8 before 8.8.15 Patch 23 and 9.x before 9.0.0 Patch 16.
A previously freed memory usage in WebGL in Google Chrome versions prior to 91.0.4472.114, allowed a remote attacker to potentially exploit stack corruption via a crafted HTML page