Welcome at this community portal @anant.saraswat and @Mausam
Could you elaborate why you think that Liferay 6.x isn’t affected?
The official vendor advisories linked in both VTs are clearly stating “Liferay Portal before 7.3.1” respectively “Liferay Portal before 7.3.3”:
without any notes that 6.x isn’t affected or that only 7.x is affected. The same is also valid for the previous linked NVD entry which states “Liferay Portal before 7.3.3” with an assigned CPE:
cpe:2.3:a:liferay:liferay_portal:*:*:*:*:*:*:*:* Up to (excluding) 7.3.3
In such cases it needs to be assumed that all versions and not only a specific branch like 7.x is affected.
If in doubt please contact your vendor asking for clarification.