The lawsuit, filed in US District Court for the Northern District of California, alleges that the modifications have in reality reduced privacy protections for Facebook users rather than increasing it, as the company had claimed it would.
"Changes to the privacy settings that Facebook implemented and represented to increase User privacy had the outright opposite effect of resulting in the public dissemination of personal information that was originally private," the lawsuit claimed.
Facebook's messaging around the changes were "misleading, confusing and disingenuous", said the lawsuit, which seeks unspecified monetary damages from the company.
Facebook did not respond immediately for a request for comment.
The changes referred to in the lawsuit were made by Facebook as part of what it said was an attempt to give users greater control over their personal data.
As part of the revamp, Facebook introduced a privacy configuration wizard to allow users to set their privacy preferences.
The social network said the revisions would make it far simpler for users to set their privacy preferences and enable them to make more informed choices concerning the use of their personal data.
However, the lawsuit, which was filed by five Facebook users on behalf of all Facebook users, alleged that the company's modifications have only resulted in more personal data being pushed out to the internet while making privacy options even harder to exercise.
Prior to Facebook's modifications last year, the only personal information that was available by default via public search was the user's name and the networks that the user belonged to.
Users had the option of deciding whether they wanted other pieces of information, such as their photos an friend listings, available publicly the lawsuit said.
However, after the revision, the information that Facebook makes publicly available by default includes user names, photos, friend's listing, the names of any organisations and products that a user might support, as well as geographic data and other information.
In total there are at least 29 privacy settings spread out over numerous web pages that users need to contend with, the lawsuit alleges.
"The privacy setting procedures are grossly ineffective and users are misled into allowing Facebook to having their personal information easily accessed for commercial use, exposing them to identity theft, harassment, embarrassment, intrusion and all types of cybercrime," it says.
The revisions also caused privacy settings to default to a setting allowing more personal information than before to now be available to third-party application developers and search engines such as Google, the complaint alleged.
The one-click option that users had available previously for controlling third-party access to their personal data has been replaced by a more complicated opt-out process, and even then there is no realistic option for restricting third-party access to personal information, the suit says.
The complaints in the lawsuit echo concerns expressed by several privacy advocates immediately after Facebook announced its revamp.
In a blog, the Electronic Frontier Foundation warned that the ostensible privacy changes were intended to push more user data out by default rather than less.
"The Facebook privacy transition tool is clearly designed to push users to share much more of their Facebook info with everyone, a worrisome development that will likely cause a major shift in privacy level for most of Facebook's users, whether intentionally or inadvertently," the EFF said.