In Legion of the Bouncy Castle BC before 1.55 and BC-FJA before 1.0.2, attackers can obtain sensitive information about a private exponent because of Observable Differences in Behavior to Error Inputs. This occurs in org.bouncycastle.crypto.encodings.OAEPEncoding. Sending invalid ciphertext that decrypts to a short payload in the OAEP Decoder could result in the throwing of an early exception, potentially leaking some information about the private exponent of the RSA private key performing the encryption.
github.com/bcgit/bc-java/commit/930f8b274c4f1f3a46e68b5441f1e7fadb57e8c1
github.com/bcgit/bc-java/wiki/CVE-2020-26939
lists.apache.org/thread.html/r8c36ba34e80e05eecb1f80071cc834d705616f315b634ec0c7d8f42e@%3Cissues.solr.apache.org%3E
lists.debian.org/debian-lts-announce/2020/11/msg00007.html
nvd.nist.gov/vuln/detail/CVE-2020-26939
security.netapp.com/advisory/ntap-20201202-0005