Change of Information on a Frozen Credit Report

Even if you have placed a security freeze on your credit report it is possible that you may get a notification of a change of information on your credit report.  In most cases you do not need to panic on getting such a notification because it is most likely to have come from one of your existing lenders.  It is more than possible that during the course of sending updated information about the credit account on a few lenders may have made the typographical error such as misspelling your name, transposing digits in a Social Security number or getting your street address wrong.  No new information can come from a new lender as no new lender can you your credit report because of the security freeze.
In case you suspect identity theft and fraud, you should understand that it could be possible almost certainly if the person who was trying to deliberately change information on your credit account was an employee of one of your creditors.  That way they would have access to records to change your account.  Another way could be if someone had enough resources to produce extremely accurate and convincing identifying documents good enough to convince the credit bureau that they were dealing with the owner of the credit report and verify that it was in fact you who was requesting the change in the information.
Even if the credit report is under a security freeze the credit bureau will usually send a notification to the person whenever a request for a change in the information is made.  If the change required is a change in the address when security qualification is sent to both the prior address on record with the credit bureau as well as the new address. The credit bureau makes it a point to note to send any sensitive information in this security alert so even if this letter finds its way to the new address reported which is not right one, you do not stand at the risk of someone stealing your identity.
If you have not requested any personal change in the information on your credit report you should order a copy of your credit history. On receiving your credit report you can review the changes made on it and the sources from where they have come from.