‘Be wary of slush funds,” US Attorney Preet Bharara last week warned officials from across New York. He was focused on local abuses — but he could’ve been talking about the state Dormitory Authority.

More specifically, the authority’s State and Municipal Facilities program, or SAM — which, as Aaron Short reported in Sunday’s Post, doesn’t face new ethics rules under Gov. Cuomo’s $152.3 billion state budget.

Even though that spending plan, in 18 separate places, requires legislators who make various funding requests to attest that they have “no financial interest,” won’t receive a “financial benefit” and have “no known conflict” in connection with the grant.

Yet lawmakers don’t have to do the ethics dance when it comes to the Cuomo-controlled SAM — which the gov has expanded to what’s now a $1.54 billion slush fund.

SAM is plainly full of pork: Past outlays have gone, for example, to support half a million bucks’ worth of trees, LED street lights and other amenities for affluent Great Neck. Why no ethics rule for these projects?

Heck, the Dormitory Authority never even spells out which lawmaker requested which “economic development” project.

Letting politicians spend money while leaving no fingerprints is an invitation to corruption: It was key to the corruption that earned former Assembly Speaker Shelly Silver a hefty federal prison sentence.

Cuomo’s plainly right to want tighter ethics rules for such spending. But he should be insisting the rules apply to spending via the Dormitory Authority and indeed to the entire executive — not just the Legislature.