CWMBS $596.4MM Mtge P-T Ctfs Series 2003-15 Rated By Fitch Ratings.

Business Editors

NEW YORK--(BUSINESS WIRE)--May 1, 2003

CWMBS, Inc.'s mortgage pass-through certificates, CHL Mortgage Pass-Through Trust 2003-15 Classes 1-A-1, 1-A-2, 2-A-1, 2-A-2, A-R and PO (senior certificates, $596,448,554) are rated 'AAA' by Fitch Ratings.

The 'AAA' rating on the senior certificates reflects the 1.25% subordination provided by the classes M and B certificates. Fitch believes the above credit enhancement will be adequate to support mortgagor defaults as well as bankruptcy, fraud and special hazard losses in limited amounts. In addition, the ratings also reflect the quality of the underlying mortgage collateral, strength of the legal and financial structures and the master servicing capabilities of Countrywide Home Loans Servicing LP (Countrywide Servicing), a direct wholly owned subsidiary of Countrywide Home Loans, Inc. (CHL).

The certificates represent an ownership interest in a pool consisting of two groups of conventional, fully amortizing, 15-year fixed-rate mortgage loans, secured by first liens on one- to four-family residential properties. As of the closing date (April 30, 2003), the mortgage loans in Loan Group 1 demonstrate an approximate weighted-average original loan-to-value ratio (OLTV) of 60.37%. Approximately 50.68% of the loans were originated under a reduced documentation program. Cash-out refinance loans represent 21.40% of the mortgage pool and second homes 2.95%. The average loan balance is $507,832. The three states that represent the largest portion of mortgage loans are California (46%), New Jersey (5.54%) and Massachusetts (4.15%). As of the closing date, the mortgage loans in Loan Group 2 demonstrate an approximate weighted-average original loan-to-value ratio (OLTV) of 60.04%. Approximately 56.80% of the loans were originated under a reduced documentation program. Cash-out refinance loans represent 15.59% of the mortgage pool and second homes 1.90%. The average loan balance is $523,365. The three states that represent the largest portion of mortgage loans are California (45.56%), New Jersey (4.16%) and Texas (3.97%).

None of the mortgage loans originated in the state of Georgia are high cost or are governed under the Georgia Fair Lending Act (GFLA). For additional information on the GFLA, please see the press release issued March 14, 2003 entitled 'Fitch To Rate RMBS After Amendment To Georgia Predatory Lending Statute, GFLA', available on the Fitch Ratings web site at 'www.fitchratings.com'. In addition, none of the mortgage loans originated in the state of New York are high cost loans. For additional information on New York state anti-predatory lending legislation, please see the press release issued March 26, 2003 entitled 'Fitch: New York State Anti-Predatory Lending Legislation', also available at 'www.fitchratings.com'.

Approximately 94.11% and 5.89%, 95.44% and 4.56% of the mortgage loans as of the closing date in Loan Group 1 and 2, respectively, were originated under CHL's Standard Underwriting Guidelines and Expanded Underwriting Guidelines, respectively. Mortgage loans underwritten pursuant to the Expanded Underwriting Guidelines may have higher loan-to-value ratios, higher loan amounts, higher debt-to-income ratios and different documentation requirements than those associated with the Standard Underwriting Guidelines. In analyzing the collateral pool, Fitch adjusted its frequency of foreclosure and loss assumptions to account for the presence of these attributes.

The collateral characteristics provided are based off the mortgage loans as of the closing date. Fitch ensures that the deposits of subsequent loans conform to representations made by Countrywide Home Loans, Inc.

CWMBS purchased the mortgage loans from CHL and deposited the loans in the trust, which issued the certificates, representing undivided beneficial ownership in the trust. For federal income tax purposes, an election will be made to treat the trust fund as multiple real estate mortgage investment conduits (REMICs).