A privilege escalation vulnerability has been identified in the Scala
compilation daemon.
The compile daemon is started explicitly by the `fsc` command, or implicitly by
executing
a Scala source file as a script (e.g `scala MyScript.scala`). Note: Using the
`scala`
command to start a REPL or to run a pre-compiled class does not start the
compile daemon.
# Impact
While the compile daemon is running, an attacker with local access to the
machine can
execute code as the user that started the compile daemon, and can write
arbitrary
class files to any location on the filesystem that the user has access to.
# Affected Versions
- Scala 2.1.6-2.10.6; 2.11.0-2.11.11; 2.12.0-2.12.3
# Mitigation
- Use `scala -nocompdaemon MyScript.scala` rather than `scala MyScript.scala`
to
disable the implicit startup and use of the daemon.
- Avoid explicitly starting `fsc`
- Upgrade to Scala 2.10.7 2.11.12, 2.12.4 or higher which restricts the
sensitive file to be
readable only by the owner. These releases also change the location of the
sensitive
file: it is written in the directory `$HOME/.scalac`.
Announcement: http://scala-lang.org/news/security-update-nov17.html
Scala Downloads: http://scala-lang.org/download/
