PORTLAND, Maine (NEWS CENTER) — A major global cyber attack hit big targets Wednesday — from Russia's biggest oil company, Maersk, to companies in the Middle East to U.S.-based pharmaceutical giant Merck.

All of them were compromised by so-called "Petya" ransomware. It attacks hardware inside computers and comes on the heels of the crippling "WannaCry" attack, and is causing global panic.

The attacks also hit DLA Piper, one of the world's biggest law firms. And even though they have a big data security practice, it was no match for these cyber thieves. The breach has Maine law firms, like Portland-based Bernstein Shur strengthening their own security measures.

"Huge, global enterprises are also getting infected by these means," said Matt Kramer, the chief information officer at the law firm. "Yes, gives me pause at night and makes me that much more vigilant about what we're doing here."

Kramer, who runs all things cyber at Bernstein Shur, said he double and triple backs up the firm's data to protect client information — what he calls his top priority.

"There's lots of different telltale signs as to who the author was of that particular virus or ransomware, and they always leave behind certain telltale markers, if you will," Kramer said. "Is that for bragging rights? Yeah, sometimes it's for bragging rights. Other times it's whoever is writing the code feels like they just want to have some fun."

Unlike the WannaCry attack, experts said Petya appears to have been aimed at causing chaos rather than extorting money.

Still, experts are urging anyone who is hacked to not pay ransom for the return of their information. They said that likely won't ensure files or data is returned.

Back at Bernstein Shur, Kramer is determined to keep that from happening, making sure computers have the latest Microsoft Windows and Apple updates, as well as anti-virus software.

"If you follow these good guidelines as well as making sure you have good backups of your data, then at least you have something to fall back on if it doesn't work."

So, how can you protect yourself? After "not" ignoring all of those software updates that so many of us choose to do "later," experts said you should consider investing in an information protection company such as LifeLock or Identity Guard. It's an investment, security experts say, could save you exponentially if you are hacked.

It's believed NSA-linked tools were used in Tuesday's large-scale cyber attack.

The Department of Homeland Security is investigating and NATO is warning it could trigger "Article 5 of the North Atlantic Treaty" in the same way as a conventional military assault.