An information disclosure vulnerability for Microsoft Edge exists as a result of how strings are validated in specific scenarios, which can allow an attacker to read sensitive data from memory and thereby potentially bypass Address Space Layout Randomization (ASLR). By itself, this vulnerability does not allow arbitrary code execution. However, an attacker could use this vulnerability in conjunction with another vulnerability, such as a remote code execution vulnerability, to run arbitrary code on a target system.
Successful exploitation of the vulnerability requires a user to be logged on and running an affected version of Microsoft Edge. The user would then need to browse to a malicious site.
The security update addresses the vulnerability by helping to ensure that Microsoft Edge properly validates strings in affected scenarios.