$ apt-cache policy samba-common
samba-common:
  Installed: (none)
  Candidate: 2:4.2.14+dfsg-0+deb8u2
  Version table:
     2:4.2.14+dfsg-0+deb8u2 0
        500 http://auto.mirror.devuan.org/merged/ jessie/main amd64 Packages
     2:4.1.17+dfsg-2+deb8u2 0
        500 http://auto.mirror.devuan.org/merged/ jessie-security/main amd64 Packages

If it's in jessie already, I'd say there is no need to have it in jessie-security.

It is strange though that jessie-security is pointing to an older version.

Looks like the recent security upgrade regression fix resurrected this problem (but with another version). Now I get

$ apt-cache policy samba-common samba-common-bin
samba-common:
  Installed: 2:4.2.14+dfsg-0+deb8u2
  Candidate: 2:4.2.14+dfsg-0+deb8u2
  Version table:
     2:4.2.14+dfsg-0+deb8u2 0
        500 http://auto.mirror.devuan.org/merged/ jessie/main amd64 Packages
     2:4.1.17+dfsg-2+deb8u2 0
        500 http://auto.mirror.devuan.org/merged/ jessie-security/main amd64 Packages
samba-common-bin:
  Installed: (none)
  Candidate: 2:4.2.14+dfsg-0+deb8u5
  Version table:
     2:4.2.14+dfsg-0+deb8u5 0
        500 http://auto.mirror.devuan.org/merged/ jessie-security/main amd64 Packages
     2:4.2.14+dfsg-0+deb8u2 0
        500 http://auto.mirror.devuan.org/merged/ jessie/main amd64 Packages

Since samba-common-bin depends on a exact same version samba-common, installing the latest security upgrade is now impossible \xf0\x9f\x98\x92

Me wonders how jessie-security is updated ... \xf0\x9f\x98\x94