RixStix:
take a look & see that IS the latest download version before telling someone they did not install using a proper fileset which is why I specified the Version instead of just saying "I used the latest version"
Why couldn't that be a bug to the core causing a debug error instead of taking intended, protective action for an attempted security breach?
So, which category would you suggest this belongs?
My interpretation of the "hotfix1 version" was that modified someone that referred to either themselves or the newly created version as the hotfix1 version. There have been a few that have gone and made autoinstall versions of ZC 1.5.3 that do not operate as intended (an example is one that allows access to the admin area without providing login credentials, not the same thing being reported here, but...). I did decide to go out on a limb and assume that the version discussed was not one from this site to get straight to possible solutions rather than lobbing questions back and forth. Limb broke. :)
So, onto the other aspects of what you investigated, if not mistaken, part of the PCI scan is to see what can be done to potentially cause mischief and if successful at getting to somewhere that they shouldn't, then the scan would/should provide an alert to identify that there is a problem with the site. It appears that in one case an error did occur which would terminate further processing in presenting that portion of the page, though I am racking my brain as to how/why there is code in the languages directory to permit something going wrong, but I do remember something "special" about credit_cards.php. Can't find it in the online docs available from this site/docs, but no matter.
All that said, yeah, the messages could be from a legit PCI scan or someone posing as such. The other part of the reporting is that I think a typical review of the actor causing the trouble is supposed to include a review of said activity at least a couple of seconds, possibly a couple of minutes in advance of the error. (Have seen others suggest up to five minutes in advance of the error message.) So it could be one or more of those individuals before the log was created that could have caused it.
My initial thought for something that doesn't clearly fall within a specific category such as a question about a payment module or a shipping module is the general questions area. I have posted here before after being able to reproduce a problem that goes back to even a vanilla install (not indicated that plugins were/were not installed above). For example on ZC 1.5.1, I can't remember the specific setting necessary regarding whether to go or not go to the shopping cart after adding a product, but I think it was to not go to the cart, if a non product default item was added to the cart, then the customer was taken to the product not found page. Unfortunately for me, that had already been identified under a different description, but it was easily repeatable and was a bug with the code that has since been corrected. So, is it necessarily a bug that an error log or warning log is generated when bad data is provided to the cart? I wouldn't necessarily call the error generation a bug, now if it went on to something else unexpected/undesired, then yes I would call it a bug. If the errors arise while naturally navigating the site, yeah probably consider it a bug.
I would say though that perhaps upon this initial notification the bug report section may lead to identifying an issue that needs to be corrected, so that's why I tried to indicate that perhaps this is the right location until "proven" or determined that it is not a bug and that the code is operating as expected.
I realize/know that you've been working with ZC for a long while and hopefully there has/will be enough information associated with the setup for a more thorough investigation into this to identify if this is a bug or not... I would say that if there was mischief assumed to have occurred (ie, doubt that the visitor was PCI scanning), then the more appropriate location would have been the help I think I have been hacked area. :) but this does not appear to be the case at the moment. :)
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