According to wikipedia or https://www.us-cert.gov/ncas/alerts/TA14-290A

this is an issue with the SSL v3.0 non deterministic padding used in CBC. Is AES in CBC mode itself is un-secure or it is an issue only when used in SSLv3.0/TLS ? Can you please clarify ?

I use openssl (an old version before the poodle attack fix) aes-128-cbc mode to encrypt a file like below, openssl enc -aes-128-cbc -in test -out test.enc -K $key128 -iv $iv

Is test.enc secure as far as the poodle attack/padding oracle attack is concerned ? If not secure, how can I make it secure ? will patching openssl to the new version take care ?


  • The problem can be with (mostly) unchecked padding plus an oracle, in any cipher and mode that uses padding. SSL/TLS does not have any modes that pad other than CBC, but it does have ciphers other than AES that operate in CBC with padding. enc with a block-mode cipher uses PKCS#5/7 padding which is checked. – dave_thompson_085 Jan 28 '15 at 11:37

POODLE requires a MITM component to be successful. You need to have a long enough stream of cyphertexts before you are able to decypher the stream. Encrypting a single file does not expose MITM vectors.

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