app-crypt/yubikey-neo-manager depends on dev-qt/qtwebkit:4 which is ancient and will never see any security updates. If it's not possible to disable this and there's no upstream port available, it might be time to consider removing this package.
The YubiKey NEO Manager project page[1] has the following notice: This project is deprecated and is no longer being maintained. Use YubiKey Manager (GUI, CLI) to configure a YubiKey device. Gentoo has a package for the CLI version[2] of YubiKey Manager (app-crypt/yubikey-manager), but not for the GUI (QT5) version[3]. The GUI version also bundles the CLI version. [1] https://developers.yubico.com/yubikey-neo-manager/ [2] https://developers.yubico.com/yubikey-manager/ [3] https://developers.yubico.com/yubikey-manager-qt/
commit 79079d2910e6e15b2db97642a743dfa15e43ede9 Author: Michał Górny <mgorny@gentoo.org> AuthorDate: Mon Aug 14 09:24:42 2017 Commit: Michał Górny <mgorny@gentoo.org> CommitDate: Mon Aug 14 09:28:18 2017 app-crypt/yubikey-neo-manager: Remove last-rited pkg, #620830 app-crypt/yubikey-neo-manager/Manifest | 4 -- ...ubikey-neo-manager-fix-pyside-requirement.patch | 17 -------- app-crypt/yubikey-neo-manager/metadata.xml | 13 ------ .../yubikey-neo-manager-1.1.0-r1.ebuild | 47 --------------------- .../yubikey-neo-manager-1.1.0.ebuild | 47 --------------------- .../yubikey-neo-manager-1.2.1-r1.ebuild | 47 --------------------- .../yubikey-neo-manager-1.2.1.ebuild | 47 --------------------- .../yubikey-neo-manager-1.3.0-r1.ebuild | 49 ---------------------- .../yubikey-neo-manager-1.3.0.ebuild | 49 ---------------------- .../yubikey-neo-manager-1.4.0.ebuild | 48 --------------------- profiles/package.mask | 3 +- 11 files changed, 1 insertion(+), 370 deletions(-)