A Brooklyn-based charity that battles homelessness and HIV/AIDS was the beneficiary of world-famous graffiti artist’s tweak of a simple oil painting, to the tune of $615,000.

Housing Works found itself in possession of a Banksy-signed painting of a landscape – altered to include a Nazi – after an anonymous donation and posted it for auction online. “The Banality of the Banality of Evil,” a framed 36” x 24.5” painting, is signed by Banksy, just below the original artist’s name.

The winning bid of $615,000 came in just before the 8 p.m. deadline on Thursday, beating out the penultimate bid by $200 on BiddingForGood.com. The bidding opened on Tuesday at $74,000 and reached $100,000 within the first two hours. Within 23 hours, the bidding had eclipsed $300,000.

The bidding was fast and furious to the end, jumping from $310,400 to $350,000 with barely 15 minutes remaining, followed by 26 more bids that finally took it to $615,000. There were a total 138 bids over the two-day online auction. BiddingForGood charges a 3-percent fee for auction proceeds above $50,000, according to its website, so Housing Works can expect to net about $596,500 from the auction.

Banksy is a pseudonym for a British graffiti artist who announced an “artist’s residency” in New York City during October, featuring daily works of his art within the five boroughs via his website. The altered painting also appears on his website, www.banksyny.com. The original painting was bought at the thrift shop for $50 several months ago but then anonymously returned to Housing Works’ Gramercy thrift shop with the addition of a man in a Nazi uniform seated on a bench overlooking a serene landscape.

Housing Works operates a dozen thrift shops in Manhattan and Brooklyn. The agency, headquartered in Brooklyn, works to end homelessness and AIDS “through relentless advocacy, the provision of lifesaving services, and entrepreneurial businesses that sustain our efforts.”

“House Works cannot express how fortunate we feel to have been a part of the Banksy residency in New York. The generous donation of his artwork will allow us to do so much good for our clients dealing with the dual crisis of homelessness and AIDS that still plagues our city streets,” said David Raper, Housing Works’ senior vice president for retail businesses.

It was the highest revenue for any one item sold by Housing Works in any of its 12 thrift shops or online. Founded in 1990, the charity reported $10 million in total revenue in each of the past two years.