David West, news president for ABC, said the two men were travelling with US and Iraqi troops near Taji, 20km (12 miles) north of Baghdad, when an improvised explosive device went off.
Taji has seen a number of deadly attacks on the US military and US-trained Iraqi security forces. It was one of the biggest bases of the former Iraqi army.
Both Woodruff and Vogt suffered serious head injuries and were taken into surgery at a US military hospital in the area, the network said.
They were wearing body armour and helmets, the network said. The two had been embedded with the 4th Infantry Division and were travelling with an Iraqi army unit.
The Iraqi vehicle they were in is considered more dangerous than US vehicles. ABC said the pair were travelling in the vehicle to get the perspective of the Iraqi military.
The US military confirmed that Woodruff and Vogt were injured in an attack near Taji and said an investigation was under way.
Lieutenant Colonel Barry Johnson, a US military spokesman, said: “They were with an Iraqi army unit at the time the attack occurred and are at a US military medical facility now.”
Woodruff, 44, became co-anchor of ABC News’ World News Tonight with Elizabeth Vargas earlier this month, replacing the late Peter Jennings.
Last week, Woodruff spent three days in Israel reporting on the Palestinian elections. He was to have been in Iraq through Tuesday, according to ABC.
Woodruff, a father of four, grew up in Michigan and became a corporate lawyer in New York. He took a leave of absence to teach at a school in China, helped CBS News during the Tiananmen Square uprising and became hooked on journalism.
He has since covered the US Justice Department and reported from Iraq, Afghanistan, Belgrade and Kosovo.
“When I realised there was a job that existed in this world where I could be in the middle of huge world events and actually get paid for it, it was an epiphany for me,” Woodruff told The Associated Press in a recent interview.
Vogt, 46, is a three-time Emmy award winning cameraman from Canada, with 25 years as a professional cameraman, the last 20 based in Europe covering global events for CBC, BBC and now exclusively for ABC News. He lives in Aix-en-Provence, France.
Dozens of journalists have been injured, killed or kidnapped in Iraq since the war began.
Another journalist, Jill Carroll, a freelance reporter for The Christian Science Monitor, was kidnapped by Iraqi fighters on 7 January and is being held in Iraq.
About 250 foreigners have been taken captive since the 2003 US-led invasion that toppled Saddam Hussein, the Iraqi president, and at least 39 have been killed.