There are 2 open security issues in buster.
2 issues left for the package maintainer to handle:
It was discovered that there was a ECDSA timing attack in the libgcrypt20 cryptographic library. Version affected: 1.8.4-5, 1.7.6-2+deb9u3, and 1.6.3-2+deb8u4. Versions fixed: 1.8.5-2 and 1.6.3-2+deb8u7.
The ElGamal implementation in Libgcrypt before 1.9.4 allows plaintext recovery because, during interaction between two cryptographic libraries, a certain dangerous combination of the prime defined by the receiver's public key, the generator defined by the receiver's public key, and the sender's ephemeral exponents can lead to a cross-configuration attack against OpenPGP.
You can find information about how to handle these issues in the security team's documentation.