The captive, identified by Israeli media as Sasha Trupanov, 28, is seen speaking in Hebrew in the 30-second clip.
It was unclear when the footage, in which he is seen wearing a T-shirt, was taken.
Trupanov, a Russian-Israeli dual national, was captured on October 7 from kibbutz Nir Oz along with his mother, grandmother, and girlfriend.
The three women were freed during a truce between Hamas and Israel at the end of November, which led to the release of 105 captives.
The Palestinian resistance groups took around 250 captives during the Al-Aqsa Flood Operation in southern Israel.
Israel since Oct.7, has been conducting a brutal military campaign on the Gaza Strip, resulting in the deaths of at least 36,096 people, the majority of whom are women and children, and injuring more than 81,000 others, according to the latest figures from the Palestinian Health Ministry.
* This story was edited by Ahram Online.
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