Well, that does not look like a 'CICS' type Abend code.
Is it an IBM CICS program issuing that? (most likely not).
Looks like an internal ABEND code within the program that issued the EXEC CICS ABEND ABCODE('FOTH')Call.
So, identify the program that issued it, then look at the source code for it.
If it is not one of your programs, it maybe an OEM vendors piece of code etc.. and you will need to look that up.
Pretty straight forward
zSoftware