R is a language and environment for statistical computing and graphics.
The native R package installation mechanisms do not sufficiently validate installed source packages for path traversal.
Installation of a malicious R package could result in an arbitrary file overwrite which could result in arbitrary code execution, as might be seen with the overwrite of an authorized_keys file.
There is no known workaround at this time.
All R users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=dev-lang/R-4.0.4"