The CDDL is generally less restrictive in terms than the GPL; its not GPL-compatible, which, given the wide array of software under the GPL and the GPLs more intense restrictions make it hard to use in many places where GPL software is in use, which perhaps makes it seem restrictive in an environment where there is an unavoidable commitment to GPL software in some role which would create a requirement GPL- or GPL-compatible software, but that's a result of the of the fact that the GPL is restrictive, not the CDDL.

(The CDDL is decidedly not permissive, of course, but its a far cry from being more restrictive than the GPL.)