2023-07-17 EXIM SYSADMINS BEWARE, DEBIAN BOOKWORM IS A
MAJOR UPDATE
A warning for all sysadmin using Exim on Debian Bullseye, don't switch
to Debian Bookworm just yet.
The changelog will tell you that, for Exim 4.96-15 in Debian Bookworm:
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| The allow_insecure_tainted_data main config option and the "taint"
| log_selector were removed
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However, if you run Debian Bullseye, you never get the warning. Those
might have come with Exim in unstable/bullseye-backports:
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| Please consider exim 4.93/4.94 a *major* exim upgrade. It introduces the
| concept of tainted data read from untrusted sources, like e.g. message
| sender or recipient. This tainted data (e.g. $local_part or $domain)
| cannot be used among other things as a file or directory name or command
| name.
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| This WILL BREAK configurations which are not updated accordingly.
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