What's this CSSM Exception in my macOS 10.12.1 logs? I'm trying to clean up my mac a bit and therefore always check through logs to see what maybe unexpected or otherwise strange. This time I see way too much going on in the logs in terms of lines per second and one thing that catches my eyes quickly is these CSSM exceptions. Here's an example:

Standard    19:46:21.455829 +0100   syncdefaultsd   CSSM Exception: -2147411889 CSSMERR_CL_UNKNOWN_TAG


In this case it's from syncdefaultsd but they happen to be from differenct processes every few seconds. I've also seen them from com.apple.iCloudHelper, quicklookd, mdworker, launchservicesd and other macOS native services.

I found through google that some people posted about them already but didn't get a real answer. Thought I might find someone to help here.

Within Minutes i get thousands of these (just captured 10 minutes with nearly 9000 lines of CSSM Exceptions.
I have found these errors to relate to old keychain data references. I was able to stop most of these CSSM Exceptions from appearing by opening Keychain Access and deleting any empty keychains.


Agreed- my CSSM Exception errors went away when I got rid of some defunct Adobe Air keychain references. The references were particularly defunct, as I had recently deleted the files to which they referred, to get rid of a previous slew of log messages...!

Interestingly, Keychain Access did not immediately disappear the keychains when I asked it to delete them; I deleted them (I tried both "Reference only", and "Reference and Files" (even though I'd manually deleted the files...!)), and they remained visible. So I quit and reopened Keychain Access- and they were gone :-) And so were the CSSM log messages :-)