Twitter is the latest tech heavyweight to voice its opposition to CISA, a controversial cybersecurity bill that could hit the Senate floor as early as Tuesday.

“Security+privacy are both priorities for us and therefore we can't support #CISA as written,” Twitter’s global public policy team tweeted late Monday. “We hope to see positive changes going forward.”

The Cybersecurity Information Sharing Act (CISA) aims to bolster information sharing between private firms and the government, but has already drawn fierce criticism from some of America’s tech titans. Last week the Computer and Communications Industry Association (CCIA), which represents the likes of Amazon, Facebook, Google and Microsoft, urged the Senate to improve the Act.

“CISA’s prescribed mechanism for sharing of cyber threat information does not sufficiently protect users’ privacy or appropriately limit the permissible uses of information shared with the government,” it warned, in a blog post. “In addition, the bill authorizes entities to employ network defense measures that might cause collateral harm to the systems of innocent third parties.”

Yelp took a swipe at CISA Sunday. “Congress is trying to pass a ‘cyber security’ bill that threatens your privacy,” it tweeted, calling for opposition to the Act.

Reddit also slammed the bill via social media. “Reddit has opposed bad "cybersecurity" bills that undermine user privacy for years. We #OpposeCISA2015,” it tweeted last week.

Although the bill could hit the floor as early as Tuesday, it is unclear when the Senate might be able to advance the measure.

The Business Software Alliance has said that it does not support the three current information sharing bills pending before Congress – CISA, the Protecting Cyber Networks Act (PCNA), and the National Cybersecurity and Communications Integration Center (NCCIC).

CISA supporters, however, include the U.S. Chamber of Commerce, which says that privacy fears about the act are overblown.  “CISA has been thoughtfully crafted to protect individuals’ privacy, while providing greater legal certainty to increase the timely exchange of actionable cyber threat information,” wrote Matthew Eggers, senior director of national security and emergency preparedness at the U.S. Chamber of Commerce, in a recent blog post.

Nonetheless, the controversy over CISA looks set to continue.

“It's outrageous that Congress is even considering passing a law that would further erode Internet users' privacy and security at a time when both are already so fragile,” Evan Greer, campaign director of Internet advocacy group Fight for the Future, told FoxNews.com via email. “CISA's supporters have repeatedly claimed that the tech industry needs this legislation, but now nearly every major tech company has come out opposing it, not only because they know it won't stop cyberattacks, but also because it's supremely unpopular with their users.”

Follow James Rogers on Twitter @jamesjrogers