Social Security Protection Act of 2005 - Amends the Congressional Budget Act of 1974 to make it out of order in the House of Representatives or the Senate to consider any bill or joint resolution, or amendment thereto or conference report thereon, that: (1) reduces or has the effect of reducing any current benefits under the old-age, survivors, and disability insurance (OASDI) programs under title II of the Social Security Act; or (2) provides for or has the effect of providing for cost-of-living increases of benefits under OASDI that are less than what would be provided under it as of the day of consideration of the applicable measure.