Qt is a cross-platform GUI framework, which is used e.g. by KDE. The AMD64 x86 emulation Qt library packages Qt libraries for 32bit x86 emulation on AMD64.
The Qt versions used by the AMD64 x86 emulation Qt libraries were vulnerable to several flaws (GLSA 200708-16, GLSA 200710-28)
An attacker could trigger one of the vulnerabilities by causing a Qt application to parse specially crafted text or Unicode strings, which may lead to the execution of arbitrary code with the privileges of the user running the application.
There is no known workaround at this time.
All AMD64 x86 emulation Qt library users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=app-emulation/emul-linux-x86-qtlibs-20071114-r2"