Critical (9.8). EPSS 11% chance of exploitation in the next 30 days. Fixed in org.scala-lang:scala-library 2.13.9.
Scala 2.13.x before 2.13.9 has a Java deserialization chain in its JAR file. On its own, it cannot be exploited. There is only a risk in conjunction with Java 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.
Severity
CVSS 3.1
9.8 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
11% chance of exploitation in the next 30 days; higher than 95% of CVEs (scores of 2026-10-31)