Both of them, but particularly Cuomo, have received exceptionally high marks.
According to a Siena poll posted on March 30th with data collected 3/22 - 3/26, approval of Cuomo’s pandemic response is 87-11, including 70% approval from Republicans! DeBlasio’s is lower, but still quite good at 61-31 approval to disapproval.
The above figures are specifically about how well they've done to address the pandemic, but Cuomo’s overall approval has also improved by 54 points to a near record high of 71-23.
The Hill is also reporting on a national poll conducted by Harvard CAPS/Harris from March 24th - March 26th which shows Cuomo with a national approval rating of 45%, nearly as high as Trump with 48%. Annoyingly, I can't find that actual data anywhere, so we just have to go off the quotes they provide:
Forty-five percent of Americans say they have a favorable view of how New York Gov. Andrew Cuomo (D) is responding to the coronavirus pandemic, according to a new Harvard CAPS/Harris poll released exclusively to The Hill.
Harvard CAPS/Harris polling director Mark Penn told The Hill. "No question he is seen now as a leader at least with Democrats and not seen as partisan since he is favorable right now by 2 to 1."
Cuomo favorability in US hits 45 percent: poll
If we take Penn at is word, that would mean that his approval is 45%, disapproval is ~ 22% and no opinion is 33%. While 45% doesn't sound that high, I'd argue that it's surprising for that many people nationwide to have a positive opinion of a local politician from another state.