If you're considering or have already implemented the latest
CF updates from June 2024 (CF2023 update 8 and CF2021 update 14), you might have struggled a bit to understand completely what Adobe was getting at in the update technotes, as they can sometimes be rather terse in covering some points (worse, some folks don't even read the technotes before applying the updates). Briefly,
a key aspect of the update changes the default algorithm that CF uses--for code that does not specify one, in several CF functions, related to encryption, hashing, or randomization.
As another case where Adobe is opting to sacrifice compatibility for security, the update changes from using the very old default of CFMX_COMPAT (as the default) to using either of a couple different alternatives, depending on the function. And if you're not careful/paying attention, you could break some critical part of your app by applying this update.
TLDR; In this post, I want to share a bit more to help you understand the impact of this update (which I blogged about in June), whether you're a developer or an administrator--and whether you've applied or not yet applied the update. Even if you HAVE done it and "all seems well" (in test or even in prod), do beware there may be nasty problems waiting to bite you that could take time to crop up. I'll explain the issues, and help you find the code using these functions, then help you determine if that code is or IS NOT affected by this change. I'll also discuss some real-world scenarios and challenges, with solutions.
Finally, I'll explain an available JVM arg (-Dcoldfusion.encryption.useCFMX_COMPATAsDefault=TRUE) that can be used to revert this behavior, for those who may feel they need to sacrifice security for compatibility, so as to get to this June update and take their time to address this change in the encryption default. I also explain how the CFMX_COMPAT algorithm DOES still remain available as an option, despite what some have asserted, which may be an acceptable option to use. Then I wrap up with some thoughts on how it may not be so bad that I'm only getting this post out a few weeks after the June update.
For more, read on.
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