Adobe InCopy version 16.4 (and earlier) is affected by a Null pointer dereference vulnerability when parsing a specially crafted file. An unauthenticated attacker could leverage this vulnerability to achieve an application denial-of-service in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.
https://helpx.adobe.com/security/products/incopy/apsb21-110.html