CVE-2026-42768 Multi-RecipientInfo Bleichenbacher Oracle in CMS_decrypt() and PKCS7_decrypt()

Issue summary: The CMSdecrypt and PKCS7decrypt functions are vulnerable to Bleichenbacher-style attack when an attacker is able to provide the CMS or S/MIME messages and observe the error code and/or decryption output. Impact summary: The Bleichenbacher-style attack allows an attacker to use the...

PT-2026-47838

Issue summary: The CMS decrypt and PKCS7 decrypt functions are vulnerable to Bleichenbacher-style attack when an attacker is able to provide the CMS or S/MIME messages and observe the error code and/or decryption output. Impact summary: The Bleichenbacher-style attack allows an attacker to use th...

openssl: information disclosure in PKCS7_dataDecode and CMS_decrypt_set1_pkey

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...