user78955: Some bitcoin airdrops are asking to prove ownership on bitcoin address by sharing signature. 
My question is if one shares bitcoin address and signature is there any risk of a attacker to compute the private key with this knowledge.
Note I am using electrum wallet to generate the signature

user69241: No, there is no way to get the private key from a signature.
But someone (person B) could force you to sign a special message so that person B can pretend to person C to own that amount of bitcoins.

user38618: 
My question is if one shares bitcoin address and signature is there any risk of a attacker to compute the private key with this knowledge

While signing, the public key becomes exposed. The primary assumption is "It's impossible to find the private key which relates to a known public key", and this assumption isn't likely to be disproved (in other words, cracked) in the next 10 years.
The process of signing a message to claim airdrops is absolutely safe, as you can move your coins to a different address after claiming your airdrops.
The only risk is your privacy: They'll know how much money you have. If that's an issue, you can just mix your coins after you're done.

78955: <p>Some bitcoin airdrops are asking to prove ownership on bitcoin address by sharing signature. </p>

<p>My question is if one shares bitcoin address and signature is there any risk of a attacker to compute the private key with this knowledge.</p>

<p>Note I am using electrum wallet to generate the signature</p>
 69241: <p>No, there is no way to get the private key from a signature.</p>

<p>But someone (person B) could force you to sign a special message so that person B can pretend to person C to own that amount of bitcoins.</p>
 38618: <blockquote>
  <p>My question is if one shares bitcoin address and signature is there any risk of a attacker to compute the private key with this knowledge</p>
</blockquote>

<p>While signing, the public key becomes exposed. The primary assumption is "It's impossible to find the private key which relates to a known public key", and this assumption isn't likely to be disproved (in other words, cracked) in the next 10 years.</p>

<p>The process of signing a message to claim airdrops is absolutely safe, as you can move your coins to a different address after claiming your airdrops.</p>

<p>The only risk is your privacy: They'll know how much money you have. If that's an issue, you can just mix your coins after you're done.</p>
