GNOME Evolution through 3.28.2 is prone to OpenPGP signatures being spoofed for arbitrary messages using a specially crafted email that contains a valid signature from the entity to be impersonated as an attachment.
Exploitability
AV:NAC:LPR:NUI:RScope
S:UImpact
C:NI:HA:N6.5/CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N