It is never confirmed in cannon, however, Wormtails actions are quite suspicious, so it was likely Voldemort suspected something.
“It could be done without Harry Potter, My Lord.”
Another pause, more protracted, and then —
“Without Harry Potter?” breathed the second voice softly. “I
see . . .”
“My Lord, I do not say this out of concern for the boy!” said
Wormtail, his voice rising squeakily. “The boy is nothing to me,
nothing at all! It is merely that if we were to use another witch or
THE RIDDLE HOUSE
wizard — any wizard — the thing could be done so much more
quickly! If you allowed me to leave you for a short while — you
know that I can disguise myself most effectively — I could be back
here in as little as two days with a suitable person —”
“I could use another wizard,” said the cold voice softly, “that is
true. . . .”
“My Lord, it makes sense,” said Wormtail, sounding thoroughly
relieved now. “Laying hands on Harry Potter would be so difficult,
he is so well protected —
And as we see later Voldemort never trusted Wormtail
Voldemort raised his wand again and whirled it through the air.
A streak of what looked like molten silver hung shining in the
wand’s wake. Momentarily shapeless, it writhed and then formed
itself into a gleaming replica of a human hand, bright as moon-
light, which soared downward and fixed itself upon Wormtail’s
This hand knew that wormtail would betray him.
“You’re going to kill me?” Harry choked, attempting to prise off the
metal fingers. “After I saved your life? You owe me, Wormtail!”
The silver fingers slackened. Harry had not expected it:
His own silver fingers
were moving inexorably toward his own throat.“No —”
Without pausing to think, Harry tried to drag back the hand, but
there was no stopping it. The silver tool that Voldemort had given
his most cowardly servant had turned upon its disarmed and use-
less owner; Pettigrew was reaping his reward for his hesitation,
moment of pity; he was being strangled before their eyes.
He were see that Voldemort had taken Wormtails weakness, and potential betrayal(in the form of helping harry) into consideration, and caused the hand he created for him, to kill him(wormtail).