Jami` at-Tirmidhi 1682
جامع الترمذي#1682SahihNarrated Al-Muhallab bin Abi Sufrah: From one who heard the Prophet (ﷺ) saying: "If you suffer a surprise attack from the enemy then say: 'Ha Min, they will not be victorious.'" [Abu 'Eisa said:] There is something on this topic from Salamah bin Al-Akwa'. This is how some of them reported it from Abu Ishaq, the same as the narration of Ath-Thawri. And it has been reported from him, from Al-Muhallab bin Abi Sufrah from the Prophet (ﷺ) in Mursal form
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirSahih
Al-AlbaniSahih
Zubair Ali ZaiSahih
In-book reference: 23:13