title: Padding Oracle in PKCS7_dataDecode and CMS_decrypt_set1_pkey
description: In situations where an attacker receives automated notification of the success or failure of a decryption attempt an attacker, after sending a very large number of messages to be decrypted, can recover a CMS/PKCS7 transported encryption key or decrypt any RSA encrypted message that was encrypted with the public RSA key, using a Bleichenbacher padding oracle attack. Applications are not affected if they use a certificate together with the private RSA key to the CMS_decrypt or PKCS7_decrypt functions to select the correct recipient info to decrypt. Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c). Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k). Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s).
problem types: Padding Oracle
affected:
{
product: OpenSSL
vendor: OpenSSL
versions:
status: affected, version: Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c)
status: affected, version: Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k)
status: affected, version: Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s)
}
metrics:
other: [
content: {'lang': 'eng', 'url': 'https://www.openssl.org/policies/secpolicy.html#Low', 'value': 'Low'}
type: unknown
]