Issue with sub-addressing after upgrade to 2026-01

[wralb]

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Description

Since upgrading this morning all emails to sub-addresses (i.e. using username+sub@domain.tld) have been ending up inboxes. No config changes made today.

Issue reproduced by @DocFraggle

Steps to reproduce:

Send email to mailto:username+sub@domain.tld and observe it arrives in inbox instead of subfolder.

Logs:

N/A

Which branch are you using?

master (stable)

Which architecture are you using?

x86_64

Operating System:

Ubuntu 22.04 LTS

Server/VM specifications:

8GB, 8 Cores

Is Apparmor, SELinux or similar active?

no

Virtualization technology:

Xen

Docker version:

28.01

docker-compose version or docker compose version:

v2.10.1

mailcow version:

2026-01

Reverse proxy:

HAProxy

Logs of git diff:

Logs of iptables -L -vn:

N/A

Logs of ip6tables -L -vn:

N/A

Logs of iptables -L -vn -t nat:

N/A

Logs of ip6tables -L -vn -t nat:

N/A

DNS check:

198.252.206.1

[DocFraggle]

@DerLinkman "X-Moo-Tag: YES" is missing in the delivered mail, maybe due to the refactoring of data/conf/rspamd/lua/rspamd.local.lua in 67e7acd ?

[ReVoLt112]

Can confirm my email doesn't find their way into subfolders either

[freakhauser]

I can confirm that subadressing no longer works after updating to 2026-01. I tried sub folders as well as adding the tag to the subjects.

[DocFraggle]

The problem seems to be that the destination mail address is added to "rcpt", i.e. receipient+wordpress@receipient.tld is set as

rcpts: <receipient+wordpress@receipient.tld,receipient@receipient.tld>

The lua script of rspamd then proceeds with receipient@receipient.tld instead of receipient+wordpress@receipient.tld leading to the log entry

rspamd-mailcow-1 | 2026-01-30 08:54:26 #35(normal) lua; rspamd.local.lua:428: TAG_MOO: no tag found in recipient [receipient@receipient.tld], removing moo tag

[DocFraggle]

Ah, the refactored lua script is working with

local rcpts = task:get_recipients('smtp')

And this does NOT contain the the original sub-address like receipient+wordpress@receipient.tld but only the original maibox receipient@receipient.tld

I added a log entry:
rspamd_logger.infox("TAG_MOO rcpt is %s", rcpts)

leading to:

rspamd-mailcow-1  | 2026-01-30 09:40:17 #35(normal) lua; rspamd.local.lua:396: TAG_MOO rcpt is {[1] = {[name] = , [raw] = <receipient@receipient.tld>, [user] = receipient, [flags] = {[valid] = true}, [domain] = receipient.eu, [addr] = receipient@receipient.tld}}

So the current logic will never add the tag. @DerLinkman

[piitch]

Having the same issue

[DocFraggle]

Having the same issue

Look at my PR, you can replace the file and it will work again.

See https://community.mailcow.email/d/5786-issue-with-sub-addressing-after-upgrade-to-2026-01/7

[piitch]

Thank you for the quick fix. I will wait till it get merged so i can update normally. Isnt that bad because I am the only user ;)

[ThxGiving]

Same issue here. X-Moo-Tag is not set to yes and subtagging is not working.

[solick]

Same issue here, tag does not appear in the header anymore