I've used "sudo apt-mark hold shim-signed" to stop upgrades temporarily.
- Bug#1137098: shim-signed: Fails to install but ... eric
- Bug#1137098: shim-signed: Fails to install... Eric Valette
- Bug#1137098: shim-signed: Fails to ins... Eric Valette
- Bug#1137098: Ashish Kulkarni
- Bug#1137098: marked as done (shim-signed: ... Debian Bug Tracking System
