After researching through the hadith sources about Qom, we came up with the following ahadith:

1. . وَ فِی خُطْبَةِ الْمَلَاحِمِ لِأَمِیرِ الْمُؤْمِنِینَ ع الَّتِی خَطَبَ بِهَا بَعْدَ وَقْعَةِ الْجَمَلِ بِالْبَصْرَةِ قَالَ یَخْرُجُ الْحَسَنِیُّ صَاحِبُ طَبَرِسْتَانَ مَعَ جَمٍّ کَثِیرٍ مِنْ خَیْلِهِ وَ رَجِلِهِ حَتَّى یَأْتِیَ نَیْسَابُورَ فَیَفْتَحُهَا وَ یَقْسِمُ أَبْوَابَهَا ثُمَّ یَأْتِی أَصْبَهَانَ ثُمَّ إِلَى قُمَّ فَیَقَعُ بَیْنَهُ وَ بَیْنِ أَهْلِ قُمَّ وَقْعَةٌ عَظِیمَةٌ یُقْتَلُ فِیهَا خَلْقٌ کَثِیرٌ فَیَنْهَزِمُ أَهْلُ قُمَّ فَیَنْهَبُ الْحَسَنِیُّ أَمْوَالَهُمْ وَ یَسْبِی ذَرَارِیَّهُمْ وَ نِسَاءَهُمْ وَ یُخَرِّبُ دُورَهُمْ فَیَفْزَعُ أَهْلُ قُمَّ إِلَى جَبَلٍ یُقَالُ لَهَا وراردهار فَیُقِیمُ الْحَسَنِیُّ بِبَلَدِهِمْ أَرْبَعِینَ یَوْماً وَ یَقْتُلُ مِنْهُمْ عِشْرِینَ رَجُلًا وَ یَصْلِبُ مِنْهُمْ رَجُلَیْنِ ثُمَّ یَرْحَلُ عَنْهُمْ؛[1]

Hasani which is originally from Tabarestan (Mazandaran), starts his voyage till he reaches Neishabur, conquers it and divides it into separate regions. A furious war erupts between him and the people of Qom which causes a mass amount of deaths! Finally, the people of Qom are defeated and Hasani takes their possessions, enslaves their women and children and ruins their homes. So they hide around a mountain named “Vardarhar”. Hasani resides in their city for forty days, kills twenty of them, hangs two of them and then migrates.

In this hadith, Qom becomes a target after vast conflicts in other cities such as Esfehan and Neishabur, but this hadith is Mursal and is therefore invalid.

2. وَ رُوِیَ مَرْفُوعاً إِلَى مُحَمَّدِ بْنِ یَعْقُوبَ الْکُلَیْنِیِّ بِإِسْنَادِهِ إِلَى عَلِیِّ بْنِ مُوسَى الرِّضَا ع قَالَ إِذَا عَمَّتِ الْبُلْدَانَ الْفِتَنُ فَعَلَیْکُمْ بِقُمَّ وَ حَوَالَیْهَا وَ نَوَاحِیهَا فَإِنَّ الْبَلَاءَ مَرْفُوعٌ عَنْهَا؛[2]

Imam Reza (as) states: whenever fitnah shadows the cities, go on to Qom and seek refuge to the territory and its outskirts for punishment has been taken away from them.

According to this hadith Qom will remain safe, although, this hadith does not mention anything about Imam Mahdi’s (as) reappearance, unless we interpret fitnah as the fitnah of akhar al-zaman.

3. . وَ قَالَ أَبُو عَبْدِ اللَّهِ الْفَقِیهُ الْهَمْدَانِیُّ فِی کِتَابِ الْبُلْدَانِ إِنَّ أَبَا مُوسَى الْأَشْعَرِیَّ رَوَى أَنَّهُ سَأَلَ أَمِیرَ الْمُؤْمِنِینَ عَلِیَّ بْنَ أَبِی طَالِبٍ ع عَنْ أَسْلَمِ الْمُدُنِ وَ خَیْرِ الْمَوَاضِعِ عِنْدَ نُزُولِ الْفِتَنِ وَ ظُهُورِ السَّیْفِ فَقَالَ أَسْلَمُ الْمَوَاضِعِ یَوْمَئِذٍ أَرْضُ الْجَبَلِ فَإِذَا اضْطَرَبَتْ خُرَاسَانُ وَ وَقَعَتِ الْحَرْبُ بَیْنَ أَهْلِ جُرْجَانَ وَ طَبَرِسْتَانَ وَ خَرِبَتْ سِجِسْتَانُ فَأَسْلَمُ الْمَوَاضِعِ یَوْمَئِذٍ قَصَبَةُ قُمَّ تِلْکَ الْبَلْدَةُ الَّتِی یَخْرُجُ مِنْهَا أَنْصَارُ خَیْرِ النَّاسِ أَباً وَ أُمّاً وَ جَدّاً وَ جَدَّةً وَ عَمّاً وَ عَمَّةً تِلْکَ الَّتِی تُسَمَّى الزَّهْرَاءَ بِهَا مَوْضِعُ قَدَمِ جَبْرَئِیلَ وَ هُوَ الْمَوْضِعُ الَّذِی نَبَعَ مِنْهُ الْمَاءُ الَّذِی مَنْ شَرِبَ مِنْهُ أَمِنَ مِنَ الدَّاءِ وَ مِنْ ذَلِکَ الْمَاءِ عُجِنَ الطِّینُ الَّذِی عَمِلَ مِنْهُ کَهَیْئَةِ الطَّیْرِ وَ مِنْهُ یَغْتَسِلُ الرِّضَا ع وَ مِنْ ذَلِکَ الْمَوْضِعُ یَخْرُجُ کَبْشُ إِبْرَاهِیمَ وَ عَصَا مُوسَى وَ خَاتَمُ سُلَیْمَان‏؛[3]

In response to what city is the most secure place in the time of fitnah, war and bloodshed, Imam Ali (as) said: The most secure place in that time is the land of Jabal, so whenever Khorasan is in unrest and the people of Gorgan and Mazandaran engage in war and Sajestan is destroyed the most secure place is Qom, this is where the companions of the best people with the greatest families (Imam Mahdi) will rise. That region is also named Zahra’, where Jibra’il has set foot and the city with a fountain that cures every illness. And from this water Prophet Jesus made clay and turned it into a bird (then you breathed into it and it became a bird by My permission.[4]) Imam Reza has made ghusl from that water and Prophet Ibrahim’s ram, Moses’ cane and Sulaiman’s ring came from this sacred place.

In this hadith Qom is introduced as a city that stays secure. In the end, we can conclude that the said ahadith do not have valid sources (chains of narrators), thus we are not able to completely rely on them and cannot relate them to preceding events of the reappearance of the Imam with certainty.

However, there is a chance that this issue has been mentioned in other ahadith also that we have not came across , but we are pretty sure that the subject of your inquiry is not included in the major hadith references.