OpenSC is a tools and libraries for smart cards.
Multiple stack-based buffer overflow errors have been discovered in OpenSC.
A physically proximate attacker could possibly execute arbitrary code using a specially crafted smart card.
There is no known workaround at this time.
All OpenSC users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=dev-libs/opensc-0.11.13-r2"
Packages which depend on this library may need to be recompiled. Tools such as revdep-rebuild may assist in identifying some of these packages.