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There are lots of mixing terminology here. In short RSA Signing is Not RSA Decryption by Cornell CS.

RSA is a trapdoor permutation, unfortunately, that can be both used for encryption and signature. This makes a common confusion.

First of all, although, RSA can be used for encryption, we don't. We prefer hybrid-encryption where a public key cryptosystem is used for key exchange and the key used in the symmetric algorithm. DHKE-AES AES and RSA-KEM AES are examples.

If one really wants to send a message with RSA encryption, they should forget to use the textbook RSA, which doesn't use a padding mechanism to be secure. PKCS#1 v1.5 and OAEP padding can be used for RSA encryption. The latter is preferable since the former is hard to implement correctly that caused many attacks.

If you want to sign a message, you should use the Probabilistic Signature Scheme (PSS). And when signing we don't' sign the message, we sign the hash of the message. This is necessary since the message can be very long and for the security proof.

What happens when I encrypt something with my RSA Public Key?

If you encrypt it with the public key without padding, the cube-root attack works if the public key is 3. Now forget encryption without padding. With correct padding, you have sent the message yourself, nothing more.

I know encrypting something with my private key is used for signing. To prove that the message is indeed coming from me.

But what about if I sign something with my public key? That would mean that only I could decrypt it with my private key.

The public keys are small and assumed to be known if you really use it for signature, this means there is a digital signature forgery. An attacker takes your public key (e,n) and produce a signature forgery.

The correct terminology is not decryption it is the verification of the signature. For signatures, we have sign and verify functions.

Suppose I did this and I sent over my ciphertext (encrypted with my public key) to somebody. Will he be able to decrypt it?

For signatures, the decryption is not the operation. The verification and forgery are the operations. If you use the public key then they will make forgeries.

Final note: Although RSA enables encryption and digital signatures, we don't use the same key for the different operations. You need two different sets for this in RSA.

For the curious reader here the Dan Boneh's article on the RSA attacks.

• Twenty Years of Attacks on the RSA Cryptosystem

There are lots of mixing terminology here. In short RSA Signing is Not RSA Decryption by Cornell CS.

RSA is a trapdoor permutation, unfortunately, that can be both used for encryption and signature. This makes a common confusion.

First of all, although, RSA can be used for encryption, we don't. We prefer hybrid-encryption where a public key cryptosystem is used for key exchange and the key used in the symmetric algorithm. DHKE-AES AES and RSA-KEM AES are examples.

If one really wants to send a message with RSA encryption, they should forget to use the textbook RSA, which doesn't use a padding mechanism to be secure. PKCS#1 v1.5 and OAEP padding can be used for RSA encryption. The latter is preferable since the former is hard to implement correctly that caused many attacks.

If you want to sign a message, you should use the Probabilistic Signature Scheme (PSS). And when signing we don't' sign the message, we sign the hash of the message. This is necessary since the message can be very long and for the security proof.

What happens when I encrypt something with my RSA Public Key?

If you encrypt it with the public key without padding, the cube-root attack works if the public key is 3. Now forget encryption without padding. With correct padding, you have sent the message yourself, nothing more.

I know encrypting something with my private key is used for signing. To prove that the message is indeed coming from me.

But what about if I sign something with my public key? That would mean that only I could decrypt it with my private key.

The public keys are small and assumed to be known if you really use it for signature, this means there is a digital signature forgery. An attacker takes your public key (e,n) and produce a signature forgery.

The correct terminology is not decryption it is the verification of the signature. For signatures, we have sign and verify functions.

Suppose I did this and I sent over my ciphertext (encrypted with my public key) to somebody. Will he be able to decrypt it?

For signatures, the decryption is not the operation. The verification and forgery are the operations. If you use the public key then they will make forgeries.

Final note: Although RSA enables encryption and digital signatures, we don't use the same key for the different operations. You need two different sets for this in RSA.

For the curious reader here the Dan Boneh's article on the RSA attacks.

• Twenty Years of Attacks on the RSA Cryptosystem

There are lots of mixing terminology here. In short RSA Signing is Not RSA Decryption by Cornell CS.

RSA is a trapdoor permutation, unfortunately, that can be both used for encryption and signature. This makes a common confusion.

First of all, although, RSA can be used for encryption, we don't. We prefer hybrid-encryption where a public key cryptosystem is used for key exchange and the key used in the symmetric algorithm. HDKE-AES AES and RSA-KEM AES are examples.

If one really wants to send a message with RSA encryption, they should forget to use the textbook RSA, which doesn't use a padding mechanism to be secure. PKCS#1 v1.5 and OAEP padding can be used for RSA encryption. The latter is preferable since the former is hard to implement correctly that caused many attacks.

If you want to sign a message, you should use the Probabilistic Signature Scheme (PSS). And when signing we don't' sign the message, we sign the hash of the message. This is necessary since the message can be very long and for the security proof.

What happens when I encrypt something with my RSA Public Key?

If you encrypt it with the public key without padding, the cube-root attack works if the public key is 3. Now forget encryption without padding. With correct padding, you have sent the message yourself, nothing more.

I know encrypting something with my private key is used for signing. To prove that the message is indeed coming from me.

But what about if I sign something with my public key? That would mean that only I could decrypt it with my private key.

The public keys are small and assumed to be known if you really use it for signature, this means there is a digital signature forgery. An attacker takes your public key (e,n) and produce a signature forgery.

The correct terminology is not decryption it is the verification of the signature. For signatures, we have sign and verify functions.

Suppose I did this and I sent over my ciphertext (encrypted with my public key) to somebody. Will he be able to decrypt it?

For signatures, the decryption is not the operation. The verification and forgery are the operations. If you use the public key then they will make forgeries.

Final note: Although RSA enables encryption and digital signatures, we don't use the same key for the different operations. You need two different sets for this in RSA.

For the curious reader here the Dan Boneh's article on the RSA attacks.

• Twenty Years of Attacks on the RSA Cryptosystem

There are lots of mixing terminology here. In short RSA Signing is Not RSA Decryption by Cornell CS.

RSA is a trapdoor permutation, unfortunately, that can be both used for encryption and signature. This makes a common confusion.

First of all, although, RSA can be used for encryption, we don't. We prefer hybrid-encryption where a public key cryptosystem is used for key exchange and the key used in the symmetric algorithm. DHKE-AES AES and RSA-KEM AES are examples.

If one really wants to send a message with RSA encryption, they should forget to use the textbook RSA, which doesn't use a padding mechanism to be secure. PKCS#1 v1.5 and OAEP padding can be used for RSA encryption. The latter is preferable since the former is hard to implement correctly that caused many attacks.

If you want to sign a message, you should use the Probabilistic Signature Scheme (PSS). And when signing we don't' sign the message, we sign the hash of the message. This is necessary since the message can be very long and for the security proof.

What happens when I encrypt something with my RSA Public Key?

If you encrypt it with the public key without padding, the cube-root attack works if the public key is 3. Now forget encryption without padding. With correct padding, you have sent the message yourself, nothing more.

I know encrypting something with my private key is used for signing. To prove that the message is indeed coming from me.

But what about if I sign something with my public key? That would mean that only I could decrypt it with my private key.

The public keys are small and assumed to be known if you really use it for signature, this means there is a digital signature forgery. An attacker takes your public key (e,n) and produce a signature forgery.

The correct terminology is not decryption it is the verification of the signature. For signatures, we have sign and verify functions.

Suppose I did this and I sent over my ciphertext (encrypted with my public key) to somebody. Will he be able to decrypt it?

For signatures, the decryption is not the operation. The verification and forgery are the operations. If you use the public key then they will make forgeries.

Final note: Although RSA enables encryption and digital signatures, we don't use the same key for the different operations. You need two different sets for this in RSA.

For the curious reader here the Dan Boneh's article on the RSA attacks.

• Twenty Years of Attacks on the RSA Cryptosystem

There are lots of mixing terminology here. In short RSA Signing is Not RSA Decryption by Cornell CS.

RSA is a trapdoor permutation, unfortunately, that can be both used for encryption and signature. This makes a common confusion.

First of all, although, RSA can be used for encryption, we don't. We prefer hybrid-encryption where a public key cryptosystem is used for key exchange and the key used in the symmetric algorithm. HDKE-AES AES and RSA-KEM AES are examples.

If one really wants to send a message with RSA encryption, they should forget to use the textbook RSA, which doesn't use a padding mechanism to be secure. PKCS#1 v1.5 and OAEP padding can be used for RSA encryption. The latter is preferable since the former is hard to implement correctly that caused many attacks.

If you want to sign a message, you should use the Probabilistic Signature Scheme (PSS). And when signing we don't' sign the message, we sign the hash of the message. This is necessary since the message can be very long and for the security proof.

What happens when I encrypt something with my RSA Public Key?

If you encrypt it with the public key without padding, the cube-root attack works if the public key is 3. Now forget encryption without padding. With correct padding, you have sent the message yourself, nothing more.

I know encrypting something with my private key is used for signing. To prove that the message is indeed coming from me.

But what about if I sign something with my public key? That would mean that only I could decrypt it with my private key.

The public keys are small and know if you really use it for signature, this means there is a digital signature forgery.

The correct terminology is not decryption it is the verification of the signature. For signatures, we have sign and verify functions.

Suppose I did this and I sent over my ciphertext (encrypted with my public key) to somebody. Will he be able to decrypt it?

For signatures, the decryption is not the operation. The verification and forgery are the operations. If you use the public key then they will make forgeries.

Final note: Although RSA enables encryption and digital signatures, we don't use the same key for the different operations. You need two different sets for this in RSA.

For the curious reader here the Dan Boneh's article on the RSA attacks.

• Twenty Years of Attacks on the RSA Cryptosystem

There are lots of mixing terminology here. In short RSA Signing is Not RSA Decryption by Cornell CS.

RSA is a trapdoor permutation, unfortunately, that can be both used for encryption and signature. This makes a common confusion.

First of all, although, RSA can be used for encryption, we don't. We prefer hybrid-encryption where a public key cryptosystem is used for key exchange and the key used in the symmetric algorithm. HDKE-AES AES and RSA-KEM AES are examples.

If one really wants to send a message with RSA encryption, they should forget to use the textbook RSA, which doesn't use a padding mechanism to be secure. PKCS#1 v1.5 and OAEP padding can be used for RSA encryption. The latter is preferable since the former is hard to implement correctly that caused many attacks.

If you want to sign a message, you should use the Probabilistic Signature Scheme (PSS). And when signing we don't' sign the message, we sign the hash of the message. This is necessary since the message can be very long and for the security proof.

What happens when I encrypt something with my RSA Public Key?

If you encrypt it with the public key without padding, the cube-root attack works if the public key is 3. Now forget encryption without padding. With correct padding, you have sent the message yourself, nothing more.

I know encrypting something with my private key is used for signing. To prove that the message is indeed coming from me.

But what about if I sign something with my public key? That would mean that only I could decrypt it with my private key.

The public keys are small and assumed to be known if you really use it for signature, this means there is a digital signature forgery. An attacker takes your public key (e,n) and produce a signature forgery.

The correct terminology is not decryption it is the verification of the signature. For signatures, we have sign and verify functions.

Suppose I did this and I sent over my ciphertext (encrypted with my public key) to somebody. Will he be able to decrypt it?

For signatures, the decryption is not the operation. The verification and forgery are the operations. If you use the public key then they will make forgeries.

Final note: Although RSA enables encryption and digital signatures, we don't use the same key for the different operations. You need two different sets for this in RSA.

For the curious reader here the Dan Boneh's article on the RSA attacks.

• Twenty Years of Attacks on the RSA Cryptosystem