Deserialization of Untrusted Data
Scala 2.13.0-M5 through 2.13.8 has a Java deserialization chain in its JAR file. On its own, it cannot be exploited. There is only a risk in conjunction with LazyList object deserialization within an application. In such situations, it allows attackers to erase contents of arbitrary files, make network connections, or possibly run arbitrary code (specifically, Function0 functions) via a gadget chain.
CWE-502 - Deserialization of Untrusted Data
Deserialization of untrusted data vulnerabilities enable an attacker to replace or manipulate a serialized object, replacing it with malicious data. When the object is deserialized at the victim's end the malicious data is able to compromise the victim’s system. The exploit can be devastating, its impact may range from privilege escalation, broken access control, or denial of service attacks to allowing unauthorized access to the application's internal code and logic which can compromise the entire system.