https://www.bleepingcomputer.com/news/security/russia-runs-incomplete-slow-sloppy-vulnerability-database/

Russia's national vulnerability database (BDU) indexes and lists about a tenth of the security flaws it should be indexing on a normal basis.

This is because the Russian BDU doesn't appear to function on the same principles as the US NVD (National Vulnerability Database), according to a year-long investigation carried out by US threat intelligence firm Recorded Future.