CSFB MBS Classes Downgraded

Eleven mezzanine and subordinated tranches from five fixed-rate mortgage securitizations issued by Credit Suisse First Boston Mortgage Securities Corp. in 2002 have been by Moody's Investors Service.The downgrades were as follows: series 2002-9 group 1, class I-B-3, from Baa2 to Baa3, class I-B-4, from Ba2 to B1, and class I-B-5, from B3 to Caa2; series 2002-10 group 2, class II-B-4, from Ba3 to B2, and class II-B-5, from B3 to Ca; series 2002-18 group 1, class I-M-1, from Aa2 to A1, and class I-M-2, from Baa2 to Caa2; series 2002-19 group 2, class II-M-1, from Aa2 to A2, and class II-M-2, from A2 to Caa1; and series 2002-26 group 3, class III-M-3, from A2 to Baa2, and class III-B, from A3 to Ba1. In addition, Moody's upgraded 29 classes from seven CSFB securitizations and confirmed the ratings on 12 classes from four deals. The downgrades were attributed primarily to cumulative losses that have exceeded original expectations. "Existing credit enhancement levels may be low given the current projected losses on the underlying pools," Moody's said. The rating agency can be found online at http://www.moodys.com.