July 2 (Reuters) - General Motors on Tuesday posted a slower rise in second-quarter U.S. sales, hurt by lower fleet sales to daily rental companies and a cyber incident at CDK that impacted dealers across the country.

Overall sales rose about 0.6% to 696,086 units, compared with an increase of about 19% in the same period last year.

"Our dealers who use the CDK platform are working to meet strong customer demand under difficult circumstances. Some deliveries may be delayed until Q3," GM said.

(Reporting by Nathan Gomes in Bengaluru; Editing by Devika Syamnath)